Developer & Webmaster Tools

Utility tools for developers, designers, and webmasters: encoding and decoding (Base64, URL, HTML, JWT), hashing (MD5, SHA-1, SHA-256), code formatting, regex testing, color conversion, and more — all run in-browser with no signup required. For network diagnostics, uptime testing, and security analysis, see Network Diagnostics →

Dev Tools

Base64

Encode UTF-8 text as Base64, or decode Base64 to UTF-8 text.
URL Encoder

Percent-encode arbitrary text for safe inclusion in URLs, or decode percent-encoded text.
HTML Entities

Escape HTML special characters as entities (& < > "), or decode entities to plain text.
JSON Formatter

Pretty-print, minify, or sort-key JSON.
HTTP Headers

Fetch a URL and inspect response headers, status code, and redirect chain.
Text Diff

Compute a unified diff between two blocks of text (line-based).
URL Parser / Builder

Break a URL into its components (scheme, host, port, path, query params, fragment) or assemble one from parts.
Regex Tester

Test a regular expression against a string — shows all matches, captured groups, and highlights matches inline.
Cron Expression Parser

Translate a cron expression into next 8 scheduled run times (UTC). Supports 5-field and 6-field (with seconds) syntax.

Designer Tools

Monitor this automatically

NetTests can run these checks on a schedule, preserve historical results, compare changes over time, and alert you the moment something breaks.

Start monitoring free → See all monitoring products