# Certificate decoder

> Inspect a PEM certificate’s details and dates.

[Open tool](https://www.toolcabana.com/ba/certificate-decoder) · [Developer and data](https://www.toolcabana.com/ba/category/developer-and-data)

Tool ID: certificate-decoder. Requested language: ba. Description language: en. Complete guide translation: no; untranslated sections use English.

## Overview (en)

Certificate decoder reads a PEM X.509 certificate and returns its serial number, subject and issuer attributes, validity start and end dates in ISO format, and its extensions with their critical flags. The input must begin with a BEGIN CERTIFICATE line and stay under 100 KB. Trust, signature and revocation are not checked.

## Supported tasks (en)

Inspect a PEM certificate’s details and dates.

## Steps (en)

1. Paste the source into the input editor, or load the built-in example.
2. Check the source format before running the operation.
3. Run certificate decoder, review the output, then use the available copy or download controls.

## Settings

No additional settings.

## Limitations (en)

Text operations generally accept up to 2,000,000 characters. Individual parsers, generators and formulas apply additional limits shown by their controls.

## Example input

```text
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

```

## Privacy and connections (en)

This operation processes its source in your browser. Copy and download are explicit actions; source input is not saved in an account or history.

## Questions (en)

### How do I check when an SSL certificate expires?

Paste the PEM certificate and look at validUntil in the output, which is the expiry date in ISO format. validFrom shows when the certificate became valid.

### Does the certificate decoder verify the certificate chain?

No. It only decodes the fields. Trust, signature and revocation status are not verified, so use your TLS tooling to confirm the certificate is trusted.

### What certificate format does the decoder accept?

It accepts a PEM certificate that begins with -----BEGIN CERTIFICATE----- and is under 100 KB. Other PEM types, such as private keys or certificate requests, are rejected.

### Where is my input processed?

This operation processes its source in your browser. Copy and download are explicit actions; source input is not saved in an account or history.

### What are the input limits?

Text operations generally accept up to 2,000,000 characters. Individual parsers, generators and formulas apply additional limits shown by their controls.

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