What Is a Certificate of Analysis (CoA) for APIs?
An API certificate of analysis (CoA) is a document issued by the manufacturer that shows the test results for a specific batch of an active pharmaceutical ingredient, compared with its approved specification. It is one of the most important documents you receive with any API shipment, because it tells you whether that batch meets the quality standard you expect.
This guide explains what a CoA contains, how to read one, what to check, and the red flags that suggest a problem.
Key Takeaways
- A CoA is batch-specific. It reports the results for one batch of one product.
- It lists tests, specifications (limits), methods and actual results, and is signed by an authorised person.
- Buyers should check that the CoA matches the product, batch number, manufacturer and their own specification.
- A CoA is not a substitute for supplier qualification or your own testing.
What Is a Certificate of Analysis?
A CoA confirms that a batch was tested and states whether it complies with the specification. For APIs, the specification is usually based on a pharmacopoeia such as IP, BP, USP or Ph. Eur., or on an agreed in-house standard.
What a CoA Usually Contains
| Section | What it shows |
|---|---|
| Product name | API name, and grade or pharmacopoeia reference |
| Manufacturer details | Name and address of the manufacturing site |
| Batch number | Unique identifier linking to batch records |
| Dates | Manufacturing date and retest or expiry date |
| Batch size and quantity | Amount in the batch or consignment |
| Tests | Appearance, identification, assay, related substances, residual solvents, water content and other tests |
| Specification | The accepted limit for each test |
| Results | The actual measured values |
| Methods | Reference to the test method or pharmacopoeia |
| Conclusion | A statement that the batch complies |
| Approval | Signature, name and date of the authorised quality person |
Example Tests on an API CoA
- Description: colour and physical form
- Identification: tests confirming the API is what it says
- Assay: how much active substance is present
- Related substances: impurities and degradation products
- Residual solvents: solvents left from manufacture
- Water content: moisture level
- Physical tests: for example particle size or polymorphic form where relevant
- Microbial limits: where required
The tests and limits depend on the product and your agreed specification.
How to Read and Check a CoA
- Product and grade. Make sure the name and grade match your order.
- Manufacturer and site. Check the manufacturing site is named and matches the licence and GMP certificate.
- Batch number. It should match the label on the containers.
- Dates. Check the manufacturing date and retest or expiry date.
- Specification. Compare the listed limits with your own specification.
- Results. Confirm every result is within the limit and that results are actual values, not just the word passes.
- Methods. Check the pharmacopoeia or method reference.
- Signature. An authorised person should sign and date it.
CoA vs Other Documents
- Specification: the limits for the product. The CoA reports results against them.
- Safety Data Sheet (SDS): hazard and handling information, not quality results.
- Batch manufacturing record: the detailed internal record of how the batch was made.
- GMP certificate: shows the site’s compliance status, not a batch result.
See the full list in documents to request from an API supplier.
Red Flags on a CoA
- no manufacturer name or site address
- a missing batch number or dates
- missing tests that appear in your specification
- results shown only as complies or passes, with no values
- identical results across different batches
- no signature or an unclear signatory
- details that do not match the product, label or other documents
Retest Date vs Expiry Date
For APIs, many manufacturers state a retest date. After that date the material should be retested to confirm it still meets specification before use. Ask the supplier which they use and what stability data supports it.
CoA and Your Own Testing
Many buyers perform their own identity tests and, for critical products, full testing of incoming batches, based on their quality system and supplier risk level. See how to evaluate a pharmaceutical API supplier.
CoA Practice at Salvavidas Pharma
Salvavidas Pharma is a WHO-GMP certified pharmaceutical manufacturer and exporter based in Surat, Gujarat, India. See our API products.
Frequently Asked Questions
What does CoA stand for?
Certificate of Analysis.
Who issues a CoA for an API?
The manufacturer’s quality control and quality assurance team, signed by an authorised person.
Is a CoA the same as a specification?
No. The specification lists the limits. The CoA shows the results of testing one batch against those limits.
Can I get a sample CoA before ordering?
Often yes. Ask the supplier for a sample CoA for the product and compare it with your specification. Need a sample CoA? Contact our export team.