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Selecting Calibration Weights
Rice Lake Weighing Systems manufactures a wide selection of quality calibration weights for various applications. Use the resources below to help select the right weight for the right application.
Rice Lake offers calibration weights in a variety of configurations—kits, sets, and single weights packaged individually.
KITS
Weight kits include the test weight, a case (or vial) for the test weight, and a glove for properly handling the test weight. All cylindrical ASTM kits (excluding grip-handle weights) include their own protective case and glove set for safe handling.
SETS
Weight sets include the test weights, a case for the test weights, and a proper lifting device to handle the test weights.
Sets may be ordered in a combination often referred to as 5-2-2-1 or a 5-3-2-1.
For example, a set might include:
- (1) 50 g weight, (2) 20 g weight, and (1) 10 g weight, or
- (1) 50 g weight, (1) 30 g weight, (1) 20 g weight, and (1) 10 g weight
By reviewing the specification of the balance or weighing device and by considering the amount of weight needed for the calibration build-up procedure
a Rice Lake customer service rep can help you make this selection.

Weight Kits

Weight Sets
Custom Calibration Weights
Rice Lake offers custom test weights as individual weights, weight kits or weight sets. Our staff is ready to assist and answer your questions.
Please call 800-472-6703 for help quoting your test weight needs. Or fill out a custom calibration weight form below.
Weight Descriptions
Calibration weights are specially designed cast iron or stainless steel weights used to calibrate weighing equipment. Test weights are manufactured and laboratory compared to a certain degree of accuracy against a known standard. Using a reliable and certified test weight to calibrate a scale is an important part of maintaining your scale’s accuracy, and a necessity if using the scale in Legal for Trade applications. Rice Lake Weighing Systems manufactures a wide selection of quality test weights for various applications. Use the resources below to help select the right test weights for your application.
Cast Iron Calibration Weights

Cast iron test weights are commonly used as field standards to test industrial weighing devices, to test non-marked scales without class designation, and to check for acceptable tolerances. Cast iron test weights are painted gold if measured in metric units or silver if measured in avoirdupois units. Most test weights come with an adjusting cavity for sealing.
Approvals
NIST: Test weight capacities of 10 kilograms/20 pounds and heavier meet NIST Handbook 105-1 and Handbook 44 specifications
Styles
Available styles include grip handle, nesting slab and slotted
Classes
NIST Class F
ASTM Class 6 and 7
OIML Class M1 and M2
Stainless Steel Calibration Weights

NIST Class F stainless steel test weights are used for field standard testing for Class III scales and balances, testing non-classified scales, and checking acceptable tolerances. Most weights have a sealing cavity for adjustment, and the nominal value is marked on the test weight with an optional serial number stamp.
Approvals
NIST: Stainless steel test weights are designed to meet NIST Handbook 44 and 105-1, Class F tolerances
Styles
Available styles include cylindrical, grip handle, leaf and dish
Classes
NIST Class F
Electronic Balance Calibration Weights

Electronic balance test weights are used to calibrate Class I and II balances, and ASTM Class 4, 5 and 6 weights. Each weight is marked with the nominal value, and weights that are Class 2-4 have the option be stamped with a serial number.
Approvals
ASTM: Stainless steel weights are manufactured under ASTM E617-23 specifications and tolerances
Styles
Available styles include grip handle, cylindrical or leaf
Classes
ASTM Class 0-7
Precision Calibration Weights

Precision test weights are used to calibrate Class I and II balances and ASTM Class 4, 5 and 6 weights, for student laboratory use and rough weighing operations. Each weight is marked with the nominal value, and cylindrical weights that are Class 2-4 have the option to be stamped with a serial number.
Approvals
ASTM: Stainless steel weights are manufactured under ASTM E617-23 specifications and tolerances
Styles
Available styles include screw-knob, cylindrical or leaf
Classes
ASTM Class 0-4
Precision Laboratory Calibration Weights

Precision laboratory test weights are used to calibrate Class I and II balances, and ASTM Class 4, 5 and 6 weights. ASTM Class 0 test weights are not individually marked with their weight value or individually serialized per ASTM E617-23. Single-piece cylindrical test weights are Type I, ASTM Class 0 and OIML Class E1 and E2, and F1 and F2 with a one-piece construction. These weights have no added adjusting material. Type II designs are cylindrical weights with adjusting cavities.
Approvals
ASTM: Stainless steel weights are manufactured under ASTM E617-23 specifications and tolerances
Styles
Available styles include single-piece Type I cylindrical weights and two-piece Type II cylindrical weights
Classes
ASTM Class 0-4
OIML Class E1 and E2, F1 and F2
Purchasing Calibration Weights
Before ordering test weights and weight sets, it is important to consider your application, the environment the test weights will be housed in, what tolerance and type of test weights you need as well as if you need any official documentation. Please use the following questions below to prepare your order. If there is missing information or if you have any questions regarding what you need, please call 800-472-6703.
Application or Environment
- Please describe your application and tell us what you need to accomplish with the weight(s) or weight set.
- What is the maximum amount of weight you will need at any one time?
- What is the minimum amount of weight you will need at any one time?
- Do you need something that is custom manufactured?
- What is your budget for this project?
- Tell us about your environment. Is it:
- Indoor/outdoor?
- Wet/dry?
- Windy/still?
- Corrosive, hazardous or explosive?
- A clean room?
- An environment with biohazard, electrostatic or magnetic conditions to consider?
- An environment with other noteworthy conditions? If so, what are they?
- Are you replacing an existing weight or weight set?
- If the answer to question number 7 is yes:
- What do you like/dislike about the existing weights?
- What configuration is the existing set?
- What style is the existing set?
- What laboratory documentation is needed for the existing set?
- Does this weight set need to be Legal for Trade?
- What other precision services/equipment (recalibration, balances, accessories, static electricity) do you use?
Tolerance or Type of Weights
- What tolerance are you looking for?
- Is your tolerance driven by the equipment under test, the application, an internal specification, a document or another source?
- What "style" (ASTM, OIML, NIST) is required or preferred?
- What configuration do you need (5-2-2-1, 5-3-2-1)?
Documentation
- Do you need ISO/IEC 17025 and ISO 9000 laboratory documentation?
- If you do not need ISO/IEC 17025 and ISO 9000 laboratory documentation, do you need traceability to NIST?
- Do you need a true mass value?
- Do you need a book version of the Calibration Report?
- If you do not need any documentation, you still have the option of an RLWS Statement of Accuracy.
- If you are getting any of the laboratory documentation above, do you need a recall date?
- Your existing weights and weight sets should be recertified on a managed periodic basis. The recertification period is determined by several factors, including but not necessarily limited to, the environment, frequency of use, demands of the process, quality of the weighing devices in question, age of the weights in question and handling during use.
Cases & Serial Numbers
OIML and ASTM test weight sets larger than 500 grams, or one pound, include a hardwood case with velvet-lined pockets. Test weight sets with the largest weight of 500 grams include a precision-machined polyvinyl, crush-resistant case.
Serial numbers are not stamped on polished or milligram weights. A test weight should be more accurate than the precision of the weighing device, and it is recommended that a test weight has an accuracy of one-third of the weighing device's readability.
Weight Tolerance Charts
Weight Conversion Charts allow users to identify the weight needed to calibrate a scale or balance. Select the chart applicable for your application.
Once you have your chart, identify the nominal size based on the capacity of your scale or balance. Then, divide the display resolution by 4 to determine your maximum permissible error (MPE). That MPE will be on your nominal size row. Once you find your MPE cell, identify the column name, which will provide your weight class.
Example Use Case:
We have a 200 gram capacity balance and we want to find an ASTM weight to calibrate the balance at or near capacity.
- Find the nominal size of 200 g on the farthest left column of the table.
- Use the MPE formula: Display Resolution / 4 = MPE
- For our example: 0.001 g / 4 = 0.25 mg
- Find the cell in your nominal row with 0.25 mg
- Find the column name for that cell to determine your Class
- For our example: Class 0 ASTM weight
ASTM E617-23 (Avoirdupois)
| Nominal Size | Class 0 | Class 1 | Class 2 | Class 3 | Class 4 | Class 5 | Class 6 | Class 7 |
| mg | mg | mg | g and mg | g and mg | g and mg | g and mg | g and mg | |
| 10000 lb | 45 g | 91 g | 230 g | 450 g | 680 g | |||
| 5000 lb | 23 g | 45 g | 110 g | 230 g | 340 g | |||
| 3000 lb | 14 g | 27 g | 68 g | 140 g | 200 g | |||
| 2500 lb | 11 g | 23 g | 57 g | 110 g | 170 g | |||
| 2000 lb | 9.1 g | 18 g | 45 g | 91 g | 140 g | |||
| 1000 lb | 4.5 g | 9.1 g | 23 g | 45 g | 68 g | |||
| 500 lb | 2.3 g | 4.5 g | 11 g | 23 g | 34 g | |||
| 300 lb | 1.4 g | 2.7 g | 6.8 g | 14 g | 20 g | |||
| 200 lb | 910 mg | 1.8 g | 4.5 g | 9.1 g | 14 g | |||
| 100 lb | 57 | 110 | 230 | 450 | 910 mg | 2.3 g | 4.5 g | 6.8 g |
| 50 lb | 29 | 57 | 110 | 230 | 450 | 1.1 g | 2.3 g | 4.1 g |
| 30 lb | 17 | 32 | 68 | 140 | 270 | 680 mg | 1.4 g | 2.7 g |
| 25 lb | 14 | 28 | 57 | 110 | 230 | 570 | 1.1 g | 2.4 g |
| 20 lb | 12 | 23 | 45 | 91 | 180 | 450 | 910 mg | 2.0 g |
| 10 lb | 5.5 | 11 | 23 | 45 | 91 | 230 | 450 | 1.3 g |
| 5 lb | 2.7 | 5.4 | 11 | 23 | 45 | 110 | 230 | 780 mg |
| 3 lb | 1.7 | 3.4 | 6.8 | 14 | 27 | 68 | 140 | 580 |
| 2 lb | 1.2 | 2.3 | 4.5 | 9.1 | 18 | 45 | 91 | 440 |
| 1 lb | 0.55 | 1.1 | 2.3 | 4.5 | 9.1 | 35 | 70 | 270 |
| 0.5 lb | 0.27 | 0.54 | 1.1 | 2.3 | 4.5 | 23 | 45 | 170 |
| 0.3 lb | 0.17 | 0.34 | 0.68 | 1.4 | 2.7 | 14 | 27 | 120 |
| 0.2 lb | 0.12 | 0.23 | 0.45 | 0.91 | 1.8 | 9.0 | 18 | 97 |
| 0.1 lb | 0.055 | 0.11 | 0.23 | 0.57 | 1.1 | 4.5 | 9.1 | 59 |
| 0.05 lb | 0.037 | 0.074 | 0.11 | 0.36 | 0.77 | 2.3 | 4.5 | 37 |
| 0.03 lb | 0.029 | 0.059 | 0.083 | 0.32 | 0.59 | 1.4 | 2.7 | 26 |
| 0.02 lb | 0.024 | 0.047 | 0.070 | 0.23 | 0.45 | 0.91 | 1.8 | 20 |
| 0.01 lb | 0.017 | 0.034 | 0.054 | 0.16 | 0.34 | 0.73 | 1.5 | 12 |
| 0.005 lb | 0.017 | 0.034 | 0.054 | 0.14 | 0.27 | 0.58 | 1.2 | 7.8 |
| 0.003 lb | 0.017 | 0.034 | 0.054 | 0.11 | 0.22 | 0.50 | 0.99 | 5.4 |
| 0.002 lb | 0.015 | 0.030 | 0.049 | 0.091 | 0.19 | 0.44 | 0.87 | 4.2 |
| 0.001 lb | 0.0050 | 0.010 | 0.024 | 0.078 | 0.15 | 0.35 | 0.70 | 2.9 |
| 0.0005 lb | 0.0045 | 0.0091 | 0.023 | 0.064 | 0.13 | 0.28 | 0.56 | 2.0 |
ASTM E617-23 (Metric)
| Nominal Size | Class 000 | Class 00 | Class 0 | Class 1 | Class 2 | Class 3 | Class 4 | Class 5 | Class 6 | Class 7 |
| mg | mg | mg | mg | g and mg | g and mg | g and mg | g and mg | g and mg | g and mg | |
| 5000 kg | 25 g | 50 g | 100 g | 250 g | 500 g | 750 g | ||||
| 3000 kg | 15 g | 30 g | 60 g | 150 g | 300 g | 450 g | ||||
| 2000 kg | 10 g | 20 g | 40 g | 100 g | 200 g | 300 g | ||||
| 1000 kg | 5.0 g | 10 g | 20 g | 50 g | 100 g | 150 g | ||||
| 500 kg | 2.5 g | 5.0 g | 10 g | 25 g | 50 g | 75 g | ||||
| 300 kg | 1.5 g | 3.0 g | 6.0 g | 15 g | 30 g | 45 g | ||||
| 200 kg | 1.0 g | 2.0 g | 4.0 g | 10 g | 20 g | 30 g | ||||
| 100 kg | 500 mg | 1.0 g | 2.0 g | 5.0 g | 10 g | 15 g | ||||
| 50 kg | 13 mg | 25 mg | 63 mg | 120 mg | 250 | 500 mg | 1.0 g | 2.5 g | 5.0 g | 7.5 g |
| 30 kg | 7.5 | 15 | 38 | 75 | 150 | 300 | 600 mg | 1.5 g | 3.0 g | 5.1 g |
| 25 kg | 6.25 | 12.5 | 31 | 62 | 125 | 250 | 500 | 1.3 g | 2.5 g | 4.5 g |
| 20 kg | 5.0 | 10 | 25 | 50 | 100 | 200 | 400 | 1.0 g | 2.0 g | 3.8 g |
| 10 kg | 2.5 | 5.0 | 13 | 25 | 50 | 100 | 200 | 500 mg | 1.0 g | 2.2 g |
| 5 kg | 1.3 | 2.5 | 6.0 | 12 | 25 | 50 | 100 | 250 | 500 mg | 1.4 g |
| 3 kg | 0.75 | 1.5 | 3.8 | 7.5 | 15 | 30 | 60 | 150 | 300 | 1.0 g |
| 2 kg | 0.5 | 1.0 | 2.5 | 5.0 | 10 | 20 | 40 | 100 | 200 | 750 mg |
| 1 kg | 0.25 | 0.5 | 1.3 | 2.5 | 5.0 | 10 | 20 | 50 | 100 | 470 |
| 500 g | 0.13 | 0.25 | 0.60 | 1.2 | 2.5 | 5.0 | 10 | 35 | 70 | 300 |
| 300 g | 0.075 | 0.15 | 0.38 | 0.75 | 1.5 | 3.0 | 6.0 | 30 | 60 | 210 |
| 200 g | 0.05 | 0.10 | 0.25 | 0.50 | 1.0 | 2.0 | 4.0 | 20 | 40 | 160 |
| 100 g | 0.025 | 0.05 | 0.13 | 0.25 | 0.50 | 1.0 | 2.0 | 10 | 20 | 100 |
| 50 g | 0.015 | 0.030 | 0.060 | 0.12 | 0.25 | 0.60 | 1.2 | 5.0 | 10 | 62 |
| 30 g | 0.014 | 0.026 | 0.037 | 0.074 | 0.15 | 0.45 | 0.90 | 3.0 | 6.0 | 44 |
| 20 g | 0.013 | 0.025 | 0.037 | 0.074 | 0.10 | 0.35 | 0.70 | 2.0 | 4.0 | 33 |
| 10 g | 0.010 | 0.020 | 0.025 | 0.050 | 0.074 | 0.25 | 0.50 | 1.0 | 2.0 | 21 |
| 5 g | 0.005 | 0.010 | 0.017 | 0.034 | 0.054 | 0.18 | 0.36 | 0.75 | 1.5 | 13 |
| 3 g | 0.005 | 0.010 | 0.017 | 0.034 | 0.054 | 0.15 | 0.30 | 0.64 | 1.3 | 9.4 |
| 2 g | 0.005 | 0.010 | 0.017 | 0.034 | 0.054 | 0.13 | 0.26 | 0.56 | 1.1 | 7.0 |
| 1 g | 0.005 | 0.010 | 0.017 | 0.034 | 0.054 | 0.10 | 0.20 | 0.45 | 0.90 | 4.5 |
| 500 mg | 0.002 | 0.003 | 0.005 | 0.010 | 0.025 | 0.080 | 0.16 | 0.36 | 0.72 | 3.0 |
| 300 mg | 0.002 | 0.003 | 0.005 | 0.010 | 0.025 | 0.070 | 0.14 | 0.31 | 0.61 | 2.2 |
| 200 mg | 0.002 | 0.003 | 0.005 | 0.010 | 0.025 | 0.060 | 0.12 | 0.27 | 0.54 | 1.8 |
| 100 mg | 0.002 | 0.003 | 0.005 | 0.010 | 0.025 | 0.050 | 0.10 | 0.22 | 0.43 | 1.2 |
| 50 mg | 0.002 | 0.003 | 0.005 | 0.010 | 0.014 | 0.042 | 0.085 | 0.17 | 0.35 | 0.88 |
| 30 mg | 0.002 | 0.003 | 0.005 | 0.010 | 0.014 | 0.038 | 0.075 | 0.15 | 0.30 | 0.68 |
| 20 mg | 0.002 | 0.003 | 0.005 | 0.010 | 0.014 | 0.035 | 0.070 | 0.13 | 0.26 | 0.56 |
| 10 mg | 0.002 | 0.003 | 0.005 | 0.010 | 0.014 | 0.030 | 0.060 | 0.10 | 0.21 | 0.40 |
| 5 mg | 0.002 | 0.003 | 0.005 | 0.010 | 0.014 | 0.028 | 0.055 | 0.083 | 0.17 | |
| 3 mg | 0.002 | 0.003 | 0.005 | 0.010 | 0.014 | 0.026 | 0.052 | 0.071 | 0.14 | |
| 2 mg | 0.002 | 0.003 | 0.005 | 0.010 | 0.014 | 0.025 | 0.050 | 0.062 | 0.12 | |
| 1 mg | 0.002 | 0.003 | 0.005 | 0.010 | 0.014 | 0.025 | 0.050 | 0.050 | 0.10 | |
| 0.5 mg | 0.002 | 0.003 | 0.005 | 0.010 | 0.014 | 0.025 | 0.050 | 0.0540 | 0.080 | |
| 0.3 mg | 0.002 | 0.003 | 0.005 | 0.010 | 0.014 | 0.025 | ||||
| 0.2 mg | 0.002 | 0.003 | 0.005 | 0.010 | 0.014 | |||||
| 0.1 mg | 0.002 | 0.003 | 0.005 | 0.010 | ||||||
| 0.05 mg | 0.002 | 0.003 | 0.005 | 0.010 |
ASTM E617-23 (Avoirdupois Ounce)
| Nominal Size | Class 0 | Class 1 | Class 2 | Class 3 | Class 4 | Class 5 | Class 6 | Class 7 |
| mg | mg | mg | mg | mg | mg | mg | mg | |
| 10 oz | 0.35 | 0.70 | 1.4 | 2.8 | 5.4 | 28 | 57 | 200 |
| 8 oz | 0.27 | 0.54 | 1.1 | 2.3 | 4.5 | 23 | 45 | 170 |
| 5 oz | 0.18 | 0.35 | 0.71 | 1.4 | 2.8 | 14 | 28 | 130 |
| 4 oz | 0.14 | 0.28 | 0.57 | 1.1 | 2.3 | 11 | 23 | 110 |
| 3 oz | 0.10 | 0.21 | 0.43 | 0.91 | 1.8 | 8.5 | 17 | 90 |
| 2 oz | 0.070 | 0.14 | 0.28 | 0.64 | 1.3 | 5.7 | 11 | 70 |
| 1 oz | 0.037 | 0.074 | 0.14 | 0.43 | 0.86 | 2.8 | 5.4 | 42 |
| 1/2 oz | 0.030 | 0.060 | 0.085 | 0.30 | 0.59 | 1.4 | 2.8 | 27 |
| 1/4 oz | 0.020 | 0.041 | 0.062 | 0.20 | 0.43 | 0.84 | 1.7 | 17 |
| 1/8 oz | 0.017 | 0.034 | 0.054 | 0.16 | 0.31 | 0.67 | 1.3 | 10 |
| 1/16 oz | 0.017 | 0.034 | 0.054 | 0.12 | 0.24 | 0.50 | 1.1 | 6.5 |
| 1/32 oz | 0.014 | 0.029 | 0.047 | 0.095 | 0.19 | 0.43 | 0.87 | 4.2 |
| 1/64 oz | 0.0050 | 0.010 | 0.023 | 0.077 | 0.15 | 0.35 | 0.69 | 2.8 |
| 0.5 oz | 0.030 | 0.060 | 0.085 | 0.30 | 0.59 | 1.4 | 2.8 | 27 |
| 0.3 oz | 0.068 | 0.23 | 0.45 | 0.89 | 1.8 | 19 | ||
| 0.2 oz | 0.057 | 0.19 | 0.38 | 0.78 | 1.6 | 14 | ||
| 0.1 oz | 0.054 | 0.14 | 0.29 | 0.63 | 1.3 | 9.0 | ||
| 0.05 oz | 0.054 | 0.11 | 0.23 | 0.50 | 1.0 | 5.7 | ||
| 0.03 oz | 0.045 | 0.095 | 0.19 | 0.43 | 0.85 | 4.1 | ||
| 0.02 oz | 0.029 | 0.077 | 0.18 | 0.38 | 0.75 | 3.2 | ||
| 0.01 oz | 0.023 | 0.064 | 0.14 | 0.30 | 0.60 | 2.2 |
ASTM E617-23 (Troy Ounce)
| Nominal Size | Class 0 | Class 1 | Class 2 | Class 3 | Class 4 | Class 5 | Class 6 | Class 7 |
| mg | mg | g and mg | ||||||
| 1000 oz t | 310 mg | 620 mg | 1.6 g | 3.1 g | ||||
| 500 oz t | 160 | 310 | 780 mg | 1.6 g | ||||
| 300 oz t | 91 | 190 | 470 | 930 mg | ||||
| 200 oz t | 62 | 120 | 310 | 620 | ||||
| 100 oz t | 31 | 62 | 160 | 310 | ||||
| 50 oz t | 16 | 31 | 78 | 160 | ||||
| 30 oz t | 9.1 | 19 | 47 | 93 | ||||
| 20 oz t | 6.2 | 12 | 39 | 77 | ||||
| 10 oz t | 3.1 | 6.2 | 30 | 61 | ||||
| 5 oz t | 1.6 | 3.1 | 16 | 31 | ||||
| 3 oz t | 0.91 | 1.9 | 9.3 | 19 | ||||
| 2 oz t | 0.71 | 1.4 | 6.2 | 12 | ||||
| 1 oz t | 0.45 | 0.91 | 3.1 | 6.2 | ||||
| 0.5 oz t | 0.31 | 0.62 | 1.6 | 3.1 | ||||
| 0.3 oz t | 0.24 | 0.49 | 0.92 | 1.8 | ||||
| 0.2 oz t | 0.20 | 0.40 | 0.80 | 1.6 | ||||
| 0.1 oz t | 0.15 | 0.30 | 0.65 | 1.3 | ||||
| 0.05 oz t | 0.12 | 0.23 | 0.52 | 1.0 | ||||
| 0.03 oz t | 0.097 | 0.19 | 0.44 | 0.88 | ||||
| 0.02 oz t | 0.084 | 0.17 | 0.39 | 0.77 | ||||
| 0.01 oz t | 0.071 | 0.14 | 0.31 | 0.62 | ||||
| 0.005 oz t | 0.056 | 0.11 | 0.25 | 0.50 |
ASTM E617-23 (Pennyweight)
| Nominal Size | Class 0 | Class 1 | Class 2 | Class 3 | Class 4 | Class 5 | Class 6 | Class 7 |
| mg | mg | g and mg | ||||||
| 10000 dwt | 155 | 310 | 780 | 1.6 g | ||||
| 5000 dwt | 78 | 160 | 390 | 780 mg | ||||
| 3000 dwt | 47 | 91 | 230 | 470 | ||||
| 2000 dwt | 31 | 62 | 160 | 310 | ||||
| 1000 dwt | 16 | 31 | 78 | 160 | ||||
| 500 dwt | 7.8 | 16 | 43 | 87 | ||||
| 300 dwt | 4.7 | 9.1 | 34 | 68 | ||||
| 200 dwt | 3.1 | 6.2 | 30 | 61 | ||||
| 100 dwt | 1.6 | 3.1 | 16 | 31 | ||||
| 50 dwt | 0.78 | 1.6 | 7.8 | 16 | ||||
| 30 dwt | 0.58 | 1.2 | 4.7 | 9.3 | ||||
| 20 dwt | 0.46 | 0.91 | 3.1 | 6.2 | ||||
| 10 dwt | 0.31 | 0.62 | 1.6 | 3.1 | ||||
| 5 dwt | 0.22 | 0.44 | 0.89 | 1.7 | ||||
| 3 dwt | 0.17 | 0.34 | 0.73 | 1.5 | ||||
| 2 dwt | 0.15 | 0.3 | 0.65 | 1.3 | ||||
| 1 dwt | 0.12 | 0.23 | 0.52 | 1.0 |
ASTM E617-23 (Grain)
| Nominal Size | Class 0 | Class 1 | Class 2 | Class 3 | Class 4 | Class 5 | Class 6 | Class 7 |
| mg | mg | mg | mg | |||||
| 10000 gr | 6.5 | 13 | 36 | 79 | ||||
| 5000 gr | 3.2 | 6.5 | 31 | 61 | ||||
| 3000 gr | 1.9 | 3.9 | 19 | 39 | ||||
| 2000 gr | 1.3 | 2.6 | 13 | 26 | ||||
| 1000 gr | 0.71 | 1.4 | 6.5 | 13 | ||||
| 500 gr | 0.48 | 0.91 | 3.2 | 6.5 | ||||
| 300 gr | 0.35 | 0.65 | 1.9 | 3.9 | ||||
| 200 gr | 0.28 | 0.57 | 1.3 | 2.6 | ||||
| 100 gr | 0.20 | 0.40 | 0.82 | 1.6 | ||||
| 50 gr | 0.15 | 0.30 | 0.65 | 1.3 | ||||
| 30 gr | 0.12 | 0.25 | 0.55 | 1.1 | ||||
| 20 gr | 0.11 | 0.21 | 0.48 | 0.91 | ||||
| 10 gr | 0.084 | 0.17 | 0.42 | 0.77 | ||||
| 5 gr | 0.071 | 0.14 | 0.31 | 0.62 | ||||
| 3 gr | 0.060 | 0.12 | 0.25 | 0.53 | ||||
| 2 gr | 0.054 | 0.11 | 0.22 | 0.45 | ||||
| 1 gr | 0.045 | 0.091 | 0.17 | 0.37 | ||||
| 0.5 gr | 0.039 | 0.078 | 0.14 | 0.31 |
ASTM E617-23 (Carat)
| Nominal Size | Class 0 | Class 1 | Class 2 | Class 3 | Class 4 | Class 5 | Class 6 | Class 7 |
| mg | mg | |||||||
| 5000 c | 10 | 20 | ||||||
| 3000 c | 6.0 | 12 | ||||||
| 2000 c | 4.0 | 8.0 | ||||||
| 1000 c | 2.0 | 4.0 | ||||||
| 500 c | 1.0 | 2.0 | ||||||
| 300 c | 0.69 | 1.3 | ||||||
| 200 c | 0.52 | 1.0 | ||||||
| 100 c | 0.35 | 0.7 | ||||||
| 50 c | 0.25 | 0.50 | ||||||
| 30 c | 0.19 | 0.40 | ||||||
| 20 c | 0.16 | 0.33 | ||||||
| 10 c | 0.13 | 0.26 | ||||||
| 5 c | 0.10 | 0.20 | ||||||
| 3 c | 0.086 | 0.17 | ||||||
| 2 c | 0.075 | 0.15 | ||||||
| 1 c | 0.060 | 0.12 | ||||||
| 0.5 c | 0.050 | 0.10 |
ASTM E617-23 (Apothecary Ounce, Dram and Scruple)
| Nominal Size | Class 0 | Class 1 | Class 2 | Class 3 | Class 4 | Class 5 | Class 6 | Class 7 |
| Apothecary Ounce | mg | |||||||
| 12 oz ap | 64 | |||||||
| 10 oz ap | 61 | |||||||
| 6 oz ap | 37 | |||||||
| 5 oz ap | 31 | |||||||
| 4 oz ap | 25 | |||||||
| 3 oz ap | 19 | |||||||
| 2 oz ap | 12 | |||||||
| 1 oz ap | 6.2 | |||||||
| Apothecary Dram | mg | |||||||
| 6 dr ap | 4.7 | |||||||
| 5 dr ap | 3.9 | |||||||
| 4 dr ap | 3.1 | |||||||
| 3 dr ap | 2.3 | |||||||
| 2 dr ap | 1.8 | |||||||
| 1 dr ap | 1.4 | |||||||
| Apothecary Scruple | mg | |||||||
| 2 s ap | 1.2 | |||||||
| 1 s ap | 0.91 |
NIST 105-1 Class F (Metric)
| Nominal Value | Class F |
| g and mg | |
| 500 kg | 50 g |
| 300 kg | 30 |
| 200 kg | 20 |
| 100 kg | 10 |
| 50 kg | 5.0 |
| 30 kg | 3.0 |
| 20 kg | 2.0 |
| 10 kg | 1.0 |
| 5 kg | 0.50 |
| 3 kg | 0.30 |
| 2 kg | 0.20 |
| 1 kg | 0.10 |
| 500 g | 70 mg |
| 300 g | 60 |
| 200 g | 40 |
| 100 g | 20 |
| 50 g | 10 |
| 30 g | 6.0 |
| 20 g | 4.0 |
| 10 g | 2.0 |
| 5 g | 1.5 |
| 3 g | 1.3 |
| 2 g | 1.1 |
| 1 g | 0.90 |
| 500 mg | 0.72 |
| 300 mg | 0.61 |
| 200 mg | 0.54 |
| 100 mg | 0.43 |
| 50 mg | 0.35 |
| 30 mg | 0.30 |
| 20 mg | 0.26 |
| 10 mg | 0.21 |
| 5 mg | 0.17 |
| 3 mg | 0.14 |
| 2 mg | 0.12 |
| 1 mg | 0.10 |
NIST 105-1 Class F (Avoirdupois Pound)
| Nominal Value | Class F |
| g and mg | |
| 10000 lb | 450 g |
| 5000 lb | 230 |
| 3000 lb | 140 |
| 2500 lb | 110 |
| 2000 lb | 91 |
| 1000 lb | 45 |
| 500 lb | 23 |
| 100 lb | 4.5 |
| 50 lb | 2.3 |
| 30 lb | 1.4 |
| 25 lb | 1.1 |
| 20 lb | 0.91 |
| 10 lb | 0.45 |
| 5 lb | 230 mg |
| 3 lb | 140 |
| 2 lb | 91 |
| 1 lb | 70 |
| 0.5 lb | 45 |
| 0.3 lb | 27 |
| 0.2 lb | 18 |
| 0.1 lb | 9.1 |
| 0.05 lb | 4.5 |
| 0.03 lb | 2.7 |
| 0.02 lb | 1.8 |
| 0.01 lb | 1.5 |
| 0.005 lb | 1.2 |
| 0.003 lb | 0.99 |
| 0.002 lb | 0.87 |
| 0.001 lb | 0.70 |
NIST 105-1 Class F (Avoirdupois Ounce)
| Nominal Value | Class F |
| F mg | |
| 8 oz | 45 |
| 4 oz | 23 |
| 2 oz | 11 |
| 1 oz | 5.4 |
| 0.5 (1/2) oz | 2.8 |
| 0.3 oz | 1.8 |
| 0.25 (1/4) oz | 1.7 |
| 0.2 oz | 1.6 |
| 0.125 (1/8) oz | 1.3 |
| 0.1 oz | 1.3 |
| 0.0625 (1/16) oz | 1.1 |
| 0.05 oz | 1.0 |
| 0.03125 (1/32) oz | 0.87 |
| 0.03 oz | 0.85 |
| 0.02 oz | 0.75 |
| 0.012325 (1/64) oz | 0.69 |
| 0.01 oz | 0.60 |
OIML RIII-I 2004 (Metric)
| Nominal Size | Class E1 | Class E2 | Class F1 | Class F2 | Class M1 | Class M2 | Class M3 |
| mg | mg | mg | mg | mg | mg | mg | |
| 5000 kg | 250,000 | 80,000 | 250,000 | 800,000 | 2,500,000 | ||
| 2000 kg | 10,000 | 30,000 | 100,000 | 300,000 | 1,000,000 | ||
| 1000 kg | 1,600 | 5,000 | 16,000 | 50,000 | 160,000 | 500,000 | |
| 500 kg | 800 | 2,500 | 8,000 | 25,000 | 80,000 | 250,000 | |
| 200 kg | 300 | 1,000 | 3,000 | 10,000 | 30,000 | 100,000 | |
| 100 kg | 160 | 500 | 1,600 | 5,000 | 16,000 | 50,000 | |
| 50 kg | 25 | 80 | 250 | 800 | 2,500 | 8,000 | 25,000 |
| 20 kg | 10 | 30 | 100 | 300 | 1,000 | 3,000 | 10,000 |
| 10 kg | 5.0 | 16 | 50 | 160 | 500 | 1,600 | 5,000 |
| 5 kg | 2.5 | 8.0 | 25 | 80 | 250 | 800 | 2,500 |
| 2 kg | 1.0 | 3.0 | 10 | 30 | 100 | 300 | 1,000 |
| 1 kg | 0.5 | 1.6 | 5.0 | 16 | 50 | 160 | 500 |
| 500 g | 0.25 | 0.8 | 2.5 | 8.0 | 25 | 80 | 250 |
| 200 g | 0.1 | 0.3 | 1.0 | 3.0 | 10 | 30 | 100 |
| 100 g | 0.05 | 0.16 | 0.5 | 1.6 | 5.0 | 16 | 50 |
| 50 g | 0.03 | 0.10 | 0.3 | 1.0 | 3.0 | 10 | 30 |
| 20 g | 0.025 | 0.08 | 0.25 | 0.8 | 2.5 | 8.0 | 25 |
| 10 g | 0.020 | 0.06 | 0.20 | 0.6 | 2.0 | 6.0 | 20 |
| 5 g | 0.016 | 0.05 | 0.16 | 0.5 | 1.6 | 5.0 | 16 |
| 2 g | 0.012 | 0.04 | 0.12 | 0.4 | 1.2 | 4.0 | 12 |
| 1 g | 0.010 | 0.03 | 0.10 | 0.3 | 1.0 | 3.0 | 10 |
| 500 mg | 0.008 | 0.025 | 0.08 | 0.25 | 0.8 | 2.5 | |
| 200 mg | 0.006 | 0.020 | 0.06 | 0.20 | 0.6 | 2.0 | |
| 100 mg | 0.005 | 0.016 | 0.05 | 0.16 | 0.5 | 1.6 | |
| 50 mg | 0.004 | 0.012 | 0.04 | 0.12 | 0.4 | ||
| 20 mg | 0.003 | 0.010 | 0.03 | 0.10 | 0.3 | ||
| 10 mg | 0.003 | 0.008 | 0.025 | 0.08 | 0.25 | ||
| 5 mg | 0.003 | 0.006 | 0.020 | 0.06 | 0.20 | ||
| 2 mg | 0.003 | 0.006 | 0.020 | 0.06 | 0.20 | ||
| 1 mg | 0.003 | 0.006 | 0.020 | 0.06 | 0.20 |
Conversion Factors
Units of Mass Not Greater than Pounds and Kilograms
| UNITS | GRAINS | APOTHECARIES SCRUPLES | PENNYWEIGHTS | AVOIRDUPOIS DRAMS | APOTHECARIES DRAMS | AVOIRDUPOIS OUNCES |
| 1 grain = | 1 | 0.05 | 0.041 666 67 | 0.036 571 43 | 0.016 666 67 | 0.002 285 714 |
| 1 apothecaries scruple = | 20 | 1 | 0.833 333 3 | 0.731 428 6 | 0.333 333 3 | 0.045 714 29 |
| 1 pennyweight = | 24 | 1.2 | 1 | 0.877 714 3 | 0.4 | 0.054 857 14 |
| 1 avoirdupois dram = | 27.343 75 | 1.367 187 5 | 1.139 323 | 1 | 0.455 729 2 | 0.062 5 |
| 1 apothecaries dram = | 60 | 3 | 2.5 | 2.194 286 | 1 | 0.137 142 9 |
| 1 avoirdupois ounce = | 437.5 | 21.875 | 18.229 17 | 16 | 7.291 667 | 1 |
| 1 apothecaries or troy ounce = | 480 | 24 | 20 | 17.554 29 | 8 | 1.097 143 |
| 1 apothecaries or troy pound = | 5760 | 288 | 240 | 210.651 4 | 96 | 13.165 71 |
| 1 avoirdupois pound = | 7000 | 350 | 291.666 7 | 256 | 116.666 7 | 16 |
| 1 milligram = | 0.015 432 36 | 0.000 771 617 9 | 0.000 643 014 9 | 0.000 564 383 4 | 0.000 257 206 0 | 0.000 035 273 96 |
| 1 gram = | 15.432 36 | 0.771 617 9 | 0.643 014 9 | 0.564 383 4 | 0.257 206 0 | 0.035 273 96 |
| 1 kilogram = | 15432.36 | 771.617 9 | 643.014 9 | 564.383 4 | 257.206 0 | 35.273 96 |
Units of Mass Not Greater than Pounds and Kilograms Cont.
| UNITS | APOTHECARIES OR TROY OUNCES | APOTHECARIES OR TROY POUNDS | AVOIRDUPOIS POUNDS | MILLIGRAMS | GRAMS | KILOGRAMS |
| 1 grain = | 0.002 083 333 | 0.000 173 611 1 | 0.000 142 857 1 | 64.798 91 | 0.064 798 91 | 0.000 064 798 91 |
| 1 apothecaries scruple = | 0.041 666 67 | 0.003 472 222 | 0.002 857 143 | 1 295.978 2 | 1.295 978 2 | 0.001 295 978 2 |
| 1 pennyweight = | 0.05 | 0.004 166 667 | 0.003 428 571 | 1 555.173 84 | 1.555 173 84 | 0.001 555 173 84 |
| 1 avoirdupois dram = | 0.056 966 15 | 0.004 747 179 | 0.003 906 25 | 1 771.845 195 312 5 | 1.771 845 195 312 5 | 0.001 771 845 195 312 5 |
| 1 apothecaries dram = | 0.125 | 0.010 416 67 | 0.008 571 429 | 3 887.934 6 | 3.887 934 6 | 0.003 887 934 6 |
| 1 avoirdupois ounce = | 0.911 458 3 | 0.075 954 86 | 0.062 5 | 28 349.523 125 | 28.349 523 125 | 0.028 349 523 125 |
| 1 apothecaries or troy ounce = | 1 | 0.083 333 333 | 0.068 571 43 | 31 103.476 8 | 31.103 476 8 | 0.031 103 476 8 |
| 1 apothecaries or troy pound = | 12 | 1 | 0.822 857 1 | 373 241.721 6 | 373.241 721 6 | 0.373 241 721 6 |
| 1 avoirdupois pound = | 14.583 33 | 1.215 278 | 1 | 453 592.37 | 453.592 37 | 0.453 592 37 |
| 1 milligram = | 0.000 032 150 75 | 0.000 002 679 229 | 0.000 002 204 623 | 1 | 0.001 | 0.000 001 |
| 1 gram = | 0.032 150 75 | 0.002 679 229 | 0.002 204 623 | 1 000 | 1 | 0.001 |
| 1 kilogram = | 32.150 75 | 2.679 229 | 2.204 623 | 1 000 000 | 1 000 | 1 |
Units of Mass Not Greater than Avoirdupois Ounces
| UNITS | AVOIRDUPOIS OUNCES | AVOIRDUPOIS POUNDS | SHORT HUNDREDWEIGHTS | SHORT TONS | LONG TONS | KILOGRAMS | METRIC TONS |
| 1 avoirdupois ounce = | 1 | 0.062 5 | 0.000 625 | 0.000 031 25 | 0.000 027 901 79 | 0.028 349 523 125 | 0.000 028 349 523 125 |
| 1 avoirdupois pound = | 16 | 1 | 0.01 | 0.000 5 | 0.000 446 428 6 | 0.453 592 37 | 0.000 453 592 37 |
| 1 short hundredweight = | 1 600 | 100 | 1 | 0.05 | 0.044 642 86 | 45.359 237 | 0.045 359 237 |
| 1 short ton = | 32 000 | 2 000 | 20 | 1 | 0.892 857 1 | 907.184 74 | 0.907 184 74 |
| 1 long ton = | 35 840 | 2 240 | 22.4 | 1.12 | 1 | 1 016.046 908 8 | 1.016 046 908 8 |
| 1 kilogram = | 35.273 96 | 2.204 623 | 0.022 046 23 | 0.001 102 311 | 0.000 984 206 5 | 1 | 0.001 |
| 1 metric ton = | 35 273.96 | 2 204.623 | 22.046 23 | 1.102 311 | 0.984 206 5 | 1 000 | 1 |
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