This website uses cookies to ensure proper functionality of the shopping cart and checkout progress. By continuing to browse the site you are agreeing to the use of cookies. Close

Professional Weighing Scales and Balances UK
Freephone: 0800 612 9007
Free mainland UK delivery for orders over £100. View details.

Individual Calibration Weights & Weight Sets

Calibration Weights are used when calibrating weighing scales and balances to ensure consistent weighing performance and accuracy. These test weights can be used for loading or quality tests when a known mass is required. Choose from our selection calibration test weights and weight sets ranging from 1g to 50kg with stainless steel, cast iron and brass variations available.

The different test weight options available can be confusing and you might well ask what the difference is between an M1 or an F1 weight, or why you might use one rather than the other. We have compiled a brief overview of the calibration weights we offer, and additional information on the importance and how to calibrate a balance with weights within our related articles below:  

M1 Class Test Weights: The most widely used test weight class on the market today. These weights are used to calibrate scales and balances where exact precision is not necessary. All class III scales use these weights for reference and calibration.

F1 Class Test Weights: Common weights used for standard precision balances and scales. These weights have a high degree of accuracy, but more cost effective than the E1 and E2 classes. Mainly used in laboratories, calibration houses and quality control areas.

E1 & E2 Class Test Weights: The most precise test weights available. These weights should be used on balances and scales with very fine resolutions, such as micro and analytical balances. Most commonly used in test and calibration houses and within the chemical and pharmaceutical industries.

We have a wide range of Adam Equipment and Kern calibration weights for sale that can be used for calibrating almost any industrial, commercial and laboratory scale or balance. All of the weights we offer can be supplied with calibration certificates as optional. Please contact us if you require more information on any of our test weights and sets.

Related Articles:

What OIML stands for and why it is important.

Just How Important is Calibration?

Internal and External Calibration: Which is right for you?

List  Grid 

Set Descending Direction
  1. star 1 selected - rating 5star 2 selected - rating 5star 3 selected - rating 5star 4 selected - rating 5star 5 selected - rating 5
    £10.00  (Ex.VAT)
    Max Capacity Range
    1g to 5000g
    Readability Range
    g to g

    Each OIML weight is an individual stainless steel weight that meet the requirements for testing to OIML standards. E2 weights offer the highest accuracy required for analytical and precision balances, M1 weights offer the lowest accuracy but are more affordable and are ideal for compact balances and bench scales.

  2. £113.00  (Ex.VAT)

    RRP £120.00 (Excl.VAT)

    Readability Range
    g to g

    OIML weight sets are a complete set of test weights that can meet the requirements for testing to OIML standards. E2 and F1 weights offer the highest accuracy required for analytical and precision balances, M1 weights offer the lowest accuracy but are more affordable and are ideal for compact balances and bench scales.

  3. £52.00  (Ex.VAT)
    Readability Range
    g to g

    E1 class milligram calibration weight manufactured by Kern. E1 test weights are suitable for calibrating balances with a high level of precision, including precision and analytical balance models. Scheduled testing of your balances with such test weights helps to guarantee your quality requirements and to maintain your quality targets.

  4. £11.00  (Ex.VAT)
    Readability Range
    g to g

    F1 milligram test weights with OIML compliance manufactured by Kern. Constructed from flat polygonal sheet in aluminium and German silver, these calibration weights are used to externally calibrate high-precision balances in milligram divisions.

  5. £23.00  (Ex.VAT)
    Max Capacity Range
    1g to 50kg
    Readability Range
    g to g

    Kern's F1 Class individual nickel plated and polished brass calibration test weights ideal for test and calibration houses, laboratories and quality control areas. F1 weights are mid-range masses used to externally calibrate precision balances and scales.

  6. £14.00  (Ex.VAT)
    Max Capacity Range
    1g to 10kg
    Readability Range
    g to g

    Kern's M1 Class Individual Finely Turned Slotted Brass Calibration Test Weights. These slotted weights are desinged to sit on hanging beam bar calibration weights and can be used to calibrate scales and balances with an under-scale hook attachment. These weights can also be used alongside force gauges and instruments working in Newtons.

  7. £30.00  (Ex.VAT)
    Max Capacity Range
    10g to 1000g
    Readability Range
    g to g

    Kern's individual M1 Class tuned beam bar brass calibration weight. Hanging beam bar weights can be customised with slotted weights for calibrating scales, balances and force measurement gauges.

  8. £65.00  (Ex.VAT)
    Max Capacity Range
    5000g to 50kg
    Readability Range
    g to g

    M1 Class cast iron block test weights manufactured by Kern. Block test weights are used for calibrating larger, industrial scales and weighing platforms with higher weight capacities. Perfect for large industrial platforms and warehouse weighing scales.

  9. £69.00  (Ex.VAT)
    Readability Range
    g to g

    M1 calibration weight box set manufactured by Kern. This boxed weight set holds a selection of turned stainless steel calibration weights for conducting full external calibration checks of scales and balances. M1 calibration weights are standard level calibration weights used for external calibration of compact, bench, industrial and retail weighing scales.

  10. £69.00  (Ex.VAT)
    Readability Range
    g to g

    M1 calibration weight box set manufactured by Kern. This turned brass range consists of a wide selection of boxed calibration weights ranging from 1mg-500mg sets to 1g to 5kg sets. Perfect for precise calibration of most standard weighing scales and balances.

Shop By!!

Shopping Options

to £
Weight Type

Scales/Balances Search

Weights Help

How to choose calibration weights

A: There are many different types of calibration weights that are used for different applications and this is not easy to answer briefly, but a good basic guide will follow this rough principle: Scales that have a coarser resolution of 0.1g, 1g and above should use M1 Class weights, 0.01g to 0.001g use F1 Class weights, whilst E2 and E1 weights should be used to calibrate balances that have a finer resolution than 0.0001g.

How to clean calibration weights

A: Weights should be dusted routinely before use, using a clean, soft-haired brush but they should not be more extensively cleaned unless it is absolutely necessary. More extensive cleaning may adjust the weight, so before cleaning measure the weight and again after cleaning to ensure it has not gone out of tolerance.

How to store calibration weights

A: Precision weights should be stored in individual boxes, wooden or plastic to protect them from dust and atmospheric pollution, and should also be stored in a suitable cupboard. Sets of weights used regularly should be stored in a suitable sized wooden or plastic box with individual compartments for each weight. Weights should not be stored on shelves or racks without adequate protection from the environment.

Is it possible for internally calibrated weighing scales to be calibrated externally as well?

A: In general yes they can - Most scales and balances with internal masses use a smaller reference weight, and can be calibrated to their full capacity using external masses.

How often should you calibrate scales and balances?

A: Most specialists would agree that scales and balances should be calibrated on a regular basis. Regular calibration is essential to the overall performance of your weighing instrument and is mandatory for businesses that conduct transactions based on weight.

Scales should be calibrated on a weekly or monthly basis, however, for more specialist requirements and instruments, such as semi-micro balances and analytical balances, we would recommend conducting daily calibration tests in order to maintain optimum results.

How would you rate this page?
We would love your feedback. Please complete our quick 3-question survey. Thank you.  Inscale
Inscale Scales for Schools 2018 - Special Offers on Selected Educational Scales and Balances