Regex for JSON Web Token

Note

A JWT’s header and payload are Base64url JSON, which always starts with eyJ. Paste one into the JWT Decoder to read it.

Matches in the example

• "eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiIxIn0.c2lnbmF0dXJl"

Token by token

1. \b a word boundary
2. eyJ the text “eyJ”
3. [A-Za-z0-9_-]+ one of: “A” to “Z”, “a” to “z”, “0” to “9”, “_” or “-”, one or more times, as many as possible
4. \. the character “.”
5. eyJ the text “eyJ”
6. [A-Za-z0-9_-]+ one of: “A” to “Z”, “a” to “z”, “0” to “9”, “_” or “-”, one or more times, as many as possible
7. \. the character “.”
8. [A-Za-z0-9_-]* one of: “A” to “Z”, “a” to “z”, “0” to “9”, “_” or “-”, zero or more times, as many as possible

Other patterns

• Email address
• URL
• IPv4 address
• UUID
• Hex color
• Date (YYYY-MM-DD)
• Time (24-hour)
• US phone number
• Phone number (E.164)
• US ZIP code
• Credit card number
• URL slug
• Username
• Strong password
• HTML tag
• Semantic version
• MAC address
• JSON Web Token
• Hashtag
• @mention
• Number
• Leading and trailing whitespace
• Repeated word
• Blank lines
• Markdown link
• Quoted string
• Domain name
• File extension
• Base64
• Trailing comma