---
id: "x509_certificate_base64"
kind: "pattern"
status: "draft"
is_pii: false
categories: ["cryptography"]
langs: ["common"]
quality: 73
url: "https://registry.apicrafter.io/datatype/x509_certificate_base64"
---

# X.509 certificate (Base64 DER without PEM lines) (`x509_certificate_base64`)

> **Draft.** Draft records have not been reviewed yet and may be incomplete or wrong; do not treat them as authoritative for legal or compliance decisions.

X.509 v3 certificate as the Base64 of its DER encoding on one line, without the -----BEGIN CERTIFICATE----- and -----END CERTIFICATE----- lines of PEM. Registries, databases and APIs often store certificates this way. The regexp follows the DER structure: a SEQUENCE with a two-byte length (MII), the tbsCertificate SEQUENCE (CC) and the version field v3 (gAwIBAgI). Certificates of version 1, which have no version field, and certificates over 16 KB are not covered.

- Pattern of: `x509_certificate`
- Personal data (PII): no
- Categories: Cryptographic identifiers (cryptography)
- Countries: global
- Languages: Common to most languages (common)

## Detection

Regular expression (Python `re`):

```
^MII[A-Za-z0-9+/]{2}[DTjz]CC[A-Za-z0-9+/]{3}gAwIBAgI[A-Za-z0-9+/]+={0,2}$
```

## Examples

- `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` — Body of the example certificate of RFC 7468, section 5.1, on one line
- `MHYwEAYHKoZIzj0CAQYFK4EEACIDYgAEn1LlwLN/KBYQRVH6HfIMTzfEqJOVztLekLchp2hi78cCaMY81FBlYs8J9l7krc+M4aBeCGYFjba+hiXttJWPL7ydlE+5UG4UNkn3Eos8EiZByi9DVsyfy9eejh+8AXgp` (invalid example) — Base64 of a public key (SubjectPublicKeyInfo), not of a certificate

## Translations

- ru: Сертификат X.509 в Base64 без PEM-заголовков: Сертификат X.509 v3 в кодировке DER, записанный в Base64 одной строкой, без строк -----BEGIN CERTIFICATE----- и -----END CERTIFICATE-----. Так сертификаты хранят реестры, базы данных и API.

## Sources

- doc: <https://www.rfc-editor.org/rfc/rfc5280#section-4.1>
- doc: <https://www.rfc-editor.org/rfc/rfc7468#section-5>

## Quality

Score 73/100. Missing: second example, mapping (Wikidata, Schema.org, ...), detector coverage.

JSON: <https://registry.apicrafter.io/api/v1/datatypes/x509_certificate_base64.json> · Edit: <https://github.com/apicrafter/metacrafter-registry/edit/main/data/datatypes/any/cryptography/x509_certificate_base64.yaml>