Developer tools

JSON formatter, color converter, subnet calculator and other tools for developers and designers.

6 tools

• JSON formatter and validator

  Pretty-print JSON with indentation, validate it with the exact line and column of any error, sort keys or minify it to one line.

• Color converter

  Convert a color between HEX, RGB, HSL, HSV, CMYK and OKLCH and check its WCAG contrast against white and black.

• Subnet calculator

  Enter an IP address with a prefix or mask to get the network address, subnet mask, broadcast address, host range and number of hosts.

• JWT decoder

  Paste a JWT to see its header and payload as readable JSON, the exp, iat and nbf times in your time zone, and whether the token has expired. The token never leaves your browser.

• Regex tester

  Test a JavaScript regular expression against your text: matches are highlighted, capture groups (named ones too) are listed, and the g, i, m, s, u, y flags are one click away. Includes replace with $1 and $<name>.

• Text compare

  Paste two versions of a text to see added, removed and changed lines, with the changed words highlighted. Side-by-side or unified view and a count of changes.