How to read a Certificate of Analysis (COA)
A COA certifies what your specific batch actually contains. Here is what each section means and what to check before you use the material.
A Certificate of Analysis (COA) is the batch-specific test report for the material you received - not a generic spec sheet. It is your proof of quality for audits, and your first check before using a chemical.
What a COA contains
- Product name, grade, and CAS number - confirm these match what you ordered.
- Batch / lot number - ties the certificate to the exact pack in your hand.
- Manufacturing / expiry or retest date - check the material is within date.
- Assay / purity - the measured purity (e.g. 99.5%), against the specification.
- Test parameters - appearance, moisture, heavy metals, residue on ignition, pH, etc., each with a spec limit and the actual result.
- Conclusion - a pass/complies statement, usually signed by QC.
What to check before using the material
- Does the batch number on the COA match the label on your container?
- Do the name, grade, and CAS match your order?
- Is every actual result within the spec limit?
- Is the material within its retest/expiry date?
If anything doesn't match, stop and contact your supplier before use. At Lubechem, a batch COA ships with every order; if you need a COA before purchase, ask us. Learn the difference between a COA, SDS and TDS.
Frequently asked questions
Is a COA the same as an SDS?
No. A COA certifies the test results for your specific batch; an SDS covers hazards, handling, and safety. You need both - a COA for quality and an SDS for safe handling.
Can I get a COA before buying?
Yes - contact us with the product and quantity and we can share the relevant batch documentation.