What this is
What is a weight and fill check?
What is a weight and fill check?
A weight and fill check is a periodic verification that the net weight or fill volume being produced matches the declared quantity on the pack. It samples measurements through a run, summarises them statistically, and checks both the average and the worst individual results against defined tolerances.
What is the difference between net weight and fill volume?
Net weight measures the mass of the contents, excluding packaging. Fill volume measures the volume of liquid or product dispensed. Which one applies depends on how the declared quantity is stated on the pack, and the check follows whichever measure is legally declared.
What is a checkweigher and why does its own verification matter?
A checkweigher is an in-line scale that weighs every pack, or a sample, and can reject an out-of-tolerance pack automatically. If it has not itself been verified against a known reference, its pass or fail decisions and every measurement recorded off it are not reliable evidence of anything.
Scope
When is a weight and fill check required?
Weight and fill checks verify quantity, what's declared against what's actually in the pack. They do not cover the pack's integrity, its label content, or contamination screening, each of which has its own instrument in this programme.
Use this template when
- A run is in progress and the stated sampling interval for weight or fill verification has been reached
- A changeover or filler adjustment has just occurred and the new setting needs confirming against the declared quantity
- A checkweigher or filler needs its verification and reject function checked before readings from it are relied on
- A customer or internal signal suggests underweight or overweight product on a specific batch
- You are running the Nonconformance and Complaints programme and quantity accuracy is the point being checked
Do not use it for
- Packaging Inspection, which checks pack integrity, seal and coding, a different attribute of the same finished pack
- Incoming Material Inspection, which checks material against specification before it is accepted into stock
- In Process Inspection, which checks product at set points against the control plan, not specifically quantity
- Metal Detection Check, which screens for foreign material, not fill accuracy
- Corrective and Preventive Action, which is where a repeated underweight or giveaway trend gets a root cause, not this record
Compliance mapping
Which NIST Handbook 133 requirements does this satisfy?
Weight and fill accuracy is governed by legal metrology rather than a quality management clause. NIST Handbook 133 and its international counterpart, OIML R87, set the sampling and tolerance method, while ISO 9001 supplies the surrounding requirement that the measuring equipment used to check it is itself verified.
| Clause | Requirement | Where it lands |
|---|---|---|
| NIST Handbook 133 | Package average must meet or exceed the declared quantity, with individual shortage bounded by a tolerable negative error | Statistics |
| NIST Handbook 133 | Sample size and count of packages below the tolerable and twice-tolerable error define the pass or fail outcome for the lot | Statistics |
| OIML R87 | International recommendation for average and minimum quantity provisions on prepackaged goods | Statistics |
| ISO 9001 cl.7.1.5.2 | Measuring equipment verified and traceable, calibrated or verified before its results are relied on | Equipment |
| ISO 9001 cl.8.5.1 | Control of production including monitoring at defined stages of the process | Measurements |
| ISO 9001 cl.8.6 | Release of products and services only after conformity has been verified | Result |
| ISO 9001 cl.9.1.1 | Monitoring, measurement, analysis and evaluation of process performance | Result |
What it does not cover
- Packaging Inspection, which checks pack integrity, seal and coding rather than declared quantity.
- Checkweigher or filler calibration record, which is the dedicated instrument verifying the equipment itself against a known reference.
- Metal Detection Check, which screens for foreign material rather than fill accuracy.
- Corrective and Preventive Action, which is where a repeated underweight or giveaway trend gets a root cause.
- Label Verification Check, which checks the declared quantity statement itself is printed correctly, not whether the pack meets it.
Global
Weight and Fill Check requirements by country
The duty to meet a declared quantity is close to universal in packaged goods trade, and the method for proving it, average plus a bounded tail, is one of the few areas where national schemes converge on essentially the same statistic.
NIST Handbook 133, Checking the Net Contents of Packaged Goods; Fair Packaging and Labeling Act
Package average must meet the declared quantity, with individual shortage bounded by a tolerable error and no package failing by more than twice that.
State weights and measures inspectors apply exactly this sampling and tolerance logic; a sample too small or a tail unread here reproduces as a failed state inspection.
Weights and Measures Act 1985; Weights and Measures (Packaged Goods) Regulations 2006
Average quantity system permitting the 'e'-mark, with a defined tolerable negative error scaled to pack size.
Trading Standards enforcement follows the same average-plus-tail logic, and a record reporting only the average does not demonstrate compliance on its own.
OIML R87, Quantity of Product in Prepackages
The international recommendation most national average-quantity systems, including the UK and EU 'e'-mark scheme, are harmonised against.
Where an export buyer runs its own metrology programme, this is the reference an auditor will expect the record to match.
How to complete it
How to complete a weight and fill check, step by step
The template calculates a percent and a mean. It does not decide whether the sample size was adequate for the batch, or whether a passing average should be trusted when the tail counts say otherwise, and those decisions determine whether the record would survive a weights and measures inspection.
The Both Directions Cost You field exists because both errors are real: underweight is a legal offence, overweight is giveaway. A filler adjusted toward the minimum acceptable weight, rather than the target fill stated on the record, has no margin left when the process drifts, and drifts in one direction only.
Number Below Twice Tolerable Error is isolated on the form precisely because it matters more than the overall Score Percent. A record that looks acceptable on Result Band but carries a nonzero count here has a failure the summary score is not built to surface.
Every measurement in the Measurements section depends on the instrument that took it. Checkweigher Verified Today marked N/A or skipped means the record cannot actually support the statistics built on top of it, whatever those statistics say.
Mean and Standard Deviation calculated from a fixed small sample regardless of run length describe that sample, not the batch. A sampling plan sized to the run is what makes the average a claim about the whole batch rather than a handful of packs.
What auditors find
Most common weight and fill check findings
Weight and fill findings concentrate on the statistics section, where an acceptable-looking summary can be built from measurements that don't actually support it.
| Finding | Clause | What fixes it |
|---|---|---|
| Checkweigher Verified Today marked N/A or skipped, so measurements from an unverified instrument are treated as valid. | ISO 9001 cl.7.1.5.2 | Make checkweigher verification a precondition for entering any Measured Weight for the run. |
| Number Below Twice Tolerable Error is nonzero but the record is still closed as Pass because the overall Score Percent looks acceptable. | NIST Handbook 133 | Any pack below twice the tolerable negative error stops the run regardless of the calculated score. |
| Filler adjusted toward the legal minimum rather than the target fill, so Giveaway Percent then runs unnecessarily high once the process drifts. | NIST Handbook 133 | Set the filler to the target fill stated on the record, and re-check giveaway after every adjustment. |
| Sample size fixed regardless of run length, so Mean and Standard Deviation describe a handful of packs rather than the batch. | OIML R87 | Apply the sampling plan for the batch size, not a fixed count regardless of run length. |
| Reject Function Tested marked N/A on a checkweigher that has an active reject mechanism fitted. | ISO 9001 cl.7.1.5.2 | Reject function is only N/A where no reject mechanism exists; otherwise it must be tested and recorded. |
| Average Meets Declared Quantity marked Yes while Number Below Tolerable Error is high, because the average does not reflect the spread. | NIST Handbook 133 | Read the average and the tail counts together; a good average with a bad tail is a fail. |
Case in point
Case in point: the average that hid the tail
A yoghurt line ran a full shift on the pot filler, taking a small sample at every checkpoint. The mean weight sat comfortably above the declared quantity for the whole run, Average Meets Declared Quantity was marked Yes each time, and the record was closed as a Pass.
A retailer's own-label audit weighed a case pulled from that batch months later and found several pots under the tolerable negative error, though the average across the case was fine. The sample size used on the line had been fixed at a handful of pots per checkpoint regardless of line speed, too small to catch the spread the filler was actually producing. A filler running an acceptable average can still send out a meaningful tail of underweight packs if the standard deviation is wide enough, and nothing on the original record had looked at the spread rather than the mean. The fix was sizing the sample to the batch and recording the tail counts, not just the mean, at every checkpoint.
The template
The template, field by field
The form exactly as it installs. Every field, option, score and conditional rule is editable, and the links to other templates come with it.
5 sections
- Reference
- QUA-017
- Archetype
- Inspection
- Record ID
- INSP-2026-000
- Scoring
- Within tolerance percent
- Direction
- High is good
- Singleton
- No
- Basis
- NIST Handbook 133, Weights and Measures
- Links
- Links Asset, Job
- Tags
- Quality, Process
- Sections
- 5
- Fields
- 49
- Follow up fields
- 4
- Repeating sections
- 1
- Links out
- 4
Header
18 fieldsCheck ID*
Auto sequence. Format CHK-2026-00000.
The record's own ID. Other templates point at this value.
Status*
Drives who this goes to next.
- Planned2 pts
- In progress2 pts
- Complete3 pts
- Deferred0 pts
- Open0 pts
- Closed3 pts
- Overdue0 pts
Date and Time*
Raised By*
Site*
Site ID*
Format SITE-000.
Links to FDN-001 Site ID
Line*
Shift*
Line Lead
Batch Number*
Numeric key joining to your ERP batch record.
Links to External system reference
Product*
Production Date*
Both Directions Cost You
Underweight is a legal offence. Overweight is money given away on every pack. Neither is acceptable and the target is the middle of the tolerance, not the bottom.
Declared Quantity*
Tolerable Negative Error
Target Fill*
Checkweigher Or Filler
Asset ID
Format AST-0000.
Links to FDN-002 Asset ID
Measurements
Repeats3 fieldsSample Number*
Measured Weight*
Within Tolerance*
- Yes3 pts
- Marginal1 pt
- No0 pts
Statistics
8 fieldsSample Size*
Mean*
Standard Deviation
Number Below Tolerable Error*
Number Below Twice Tolerable Error*
Any pack below twice the tolerable negative error is a legal failure on its own.
Average Meets Declared Quantity*
- Yes3 pts
- No0 pts
Giveaway Percent*
Overfill as a percentage. This is direct margin loss.
Giveaway Within Target*
- Yes3 pts
- Marginal1 pt
- No0 pts
Equipment
5 fieldsCheckweigher Verified Today*
- Yes2 pts
- No0 pts
- N/Aexcluded from denominator
Verification Record ID
Links to QUA-067 Check ID
Reject Function Tested*
- Pass2 pts
- Partial1 pt
- Fail0 pts
- N/Aexcluded from denominator
Filler Adjusted
- Yes3 pts
- Not needed3 pts
- No0 pts
Adjustment Detail
Result
15 fieldsItems Assessed*
Excludes anything marked N/A.
Items Failed*
Score Percent*
Calculated on submission. High is good. N/A items leave the denominator.
Result Band*
- Pass3 pts
- Caution1 pt
- Fail0 pts
Completeness Percent*
How much of the template was actually answered. A high score on a half completed form is not a high score.
Decision*
Comments
Action Required*
Raise the action record, then enter its reference here.
- No2 pts
- Yes0 pts
Priority
- High0 pts
- Medium1 pt
- Low3 pts
CAPA ID
Format CAPA-2026-00000.
Links to FDN-014 CAPA ID
Action Owner
Inspector*
Signature*
Line Lead*
Second Signature*
QUA-017 · record IDs look like INSP-2026-000 · Links Asset, Job
Open in KnowellaRun it with agents
From a document you fill in to a programme that runs itself
The form is the easy part. Keeping the checkweigher's own verification current, reading the tail counts rather than the mean, and stopping a run on a legal-level failure regardless of the overall score is the work that actually slips.
Holds the weight and fill check library against the sampling schedule, flags a twice-tolerable-error breach regardless of the calculated score, and keeps the statistics evidence trail together.
Tracks checkweigher and filler verification and calibration due dates against the linked Asset, so a measurement is never relied on from an unverified instrument.
Tracks weights and measures obligations against the jurisdictions a site ships into, and surfaces where a sampling or tolerance practice falls short of the applicable rule.
Watches for a passing average sitting alongside a nonzero twice-tolerable-error count, and raises it to the line lead rather than letting the summary score absorb it.
This template lives in KnowQuality — quality and food safety. HACCP, nonconformance, traceability, laboratory and customer complaints.
Meet KnowQuality→Glossary
Weight and Fill Check definitions and key terms
- Tolerable negative error
- The maximum amount a single pack may fall short of the declared quantity and still be acceptable.
- Twice the tolerable negative error
- A stricter limit; a pack below it fails on its own regardless of the batch average.
- Average quantity system
- The weights and measures principle that a batch's average meets the declared quantity, with individual shortfalls bounded rather than prohibited outright.
- Giveaway
- The amount by which fill exceeds the declared quantity, expressed as a percentage; excess giveaway is margin given away, not a safety margin.
- Checkweigher verification
- Confirming a checkweigher's accuracy and reject function against a known reference before its readings are relied on.
FAQ
Frequently asked questions about weight and fill check
Should the filler target the tolerance floor or the middle of the tolerance?+
The middle. Targeting the floor guarantees that ordinary process variation will push some packs under the legal minimum, whereas centring on the target gives the process room to drift in either direction without a failure.
What matters more, the average or the tail?+
Both, but the average alone can hide an unacceptable tail if the spread is wide. Look at Number Below Tolerable Error and Number Below Twice Tolerable Error specifically, not just whether the mean clears the declared quantity.
What if the checkweigher hasn't been verified today?+
Treat that as no data, not as a formality to catch up on later. Measurements taken from an unverified instrument are not reliable evidence that the pack meets or fails its declared quantity.
How is sample size decided?+
By the sampling plan appropriate to the batch size, not a fixed count applied regardless of throughput. A sample too small for the run understates the true spread of the process.
Is overweight product ever acceptable?+
Some giveaway within a small target band is normal, but a large giveaway is money given away on every pack, not a safety cushion. Giveaway Within Target exists to keep that in check, not to excuse it.
What if Number Below Twice Tolerable Error is not zero?+
That is a legal-level failure on its own. It should stop the run and be escalated regardless of what Score Percent or Result Band otherwise show.
Keep going
Related templates and programmes
Industries this is written for
Programmes this belongs to
Used together in Nonconformance and Complaints
Root Cause Analysis
Finds out why something happened rather than who was involved
Corrective and Preventive Action
The single action record used everywhere
Product Nonconformance Report
Records product that does not meet specification
Process Deviation Report
Records a process that ran outside its set limits, even where the product still passed
Hold and Release Record
Places suspect product on hold and records the decision to release, rework or scrap it
Rework Authorization
Authorises rework on nonconforming product and sets out exactly what will be done
More in Quality Inspections
Incoming Material Inspection
Checks material against specification before it is accepted into stock
First Article Inspection
Checks the first piece from a new setup or changeover against every specified characteristic
In Process Inspection
Checks product at set points during production, against the control plan
Final Product Inspection
Checks finished product before it is released to the customer
Packaging Inspection
Checks packaging integrity, labelling, coding and seal quality
Label Verification Check
Confirms the label on the line matches the product being run, including allergens, weight and date code
Written and reviewed by
Siddarth Singh
Founder & Chief Executive Officer, Knowella
Certified Safety Professional and industrial and systems engineer with more than a decade inside food supply chain, freight and manufacturing operations. This page was written against the current text of the standards it cites, not against secondary summaries of them.
- Certified Safety Professional (CSP), Board of Certified Safety Professionals
- MBA, University of Chicago Booth School of Business
- MS and BS, The Ohio State University, Industrial and Systems Engineering
- Six Sigma Black Belt
Sources and last review. Reviewed 16 August 2026 against:
- NIST Handbook 133, Checking the Net Contents of Packaged Goods
- OIML R87, Quantity of Product in Prepackages
- Weights and Measures (Packaged Goods) Regulations 2006 (UK)
- ISO 9001:2015 clauses 7.1.5 and 8.6
This page is general guidance, not legal advice. Confirm requirements with your jurisdiction’s regulator.