# getOcspUrl

## Content

# Function: getOcspUrl()

```ts
function getOcspUrl(certificatePem): string;
```

Extracts the OCSP responder URL from the given X.509 certificate.

The function parses the Authority Information Access (AIA) extension
of the certificate and returns the URI associated with the OCSP
access method, if present.

## Parameters

### certificatePem

`string`

The certificate in PEM format.

## Returns

`string`

The OCSP responder URL, or `null` if the certificate does not
contain an OCSP entry in its AIA extension.

## Remarks

Some certificates may include multiple OCSP URLs; in such cases, the
first one is returned. If the AIA extension is missing or does not
contain an OCSP access method, the function returns `null`.