ToolBench
All 32TextDeveloperConvertSecurityImagesCalculatorsDate & timeWeb

06 tools

Developer

JSON, Base64, JWT, HTML entities and regex.

01JSON FormatterFormat, indent, minify and validate JSON in your browser. Errors are reported with the parser's own message. Nothing is uploaded.→02Base64 EncoderEncode text to Base64 or decode it back, with correct UTF-8 handling for accents, CJK and emoji. Runs entirely in the browser.→03URL EncoderPercent-encode or decode URLs and query strings, showing the difference between encodeURI and encodeURIComponent.→04JWT DecoderPaste a JSON Web Token to read its header and payload as JSON, with the expiry date translated into plain UTC time. Nothing is sent anywhere.→05HTML Entity ConverterEscape the five characters that break HTML, or turn existing entities back into plain text. Useful when embedding user text in a template.→06Regex TesterType a pattern, paste sample text, and see every match highlighted with its capture groups and offsets. Runs in your browser, no round trip.→

The debugging chores

Everything here exists because a developer needed to look inside something opaque: whether a JSON payload is actually valid, what a JWT really claims, what those percent signs in a URL decode to, which characters in a snippet are HTML entities rather than text. Each one takes a copy-paste and returns an answer in under a second.

Order of operations when something breaks

Start with the data, not the code. Validate the JSON first — a payload that fails to parse never reaches your handler, so any logging you added there will stay silent. Then decode the token and compare exp against the clock, because an expired credential produces the same 401 as a wrong one. Only then look at encoding: a value that arrives truncated or double-escaped usually passed through one too many encode/decode steps.

What none of these do

They do not verify signatures, they do not fetch URLs, and they do not execute the code you paste. Decoding a token proves only that it is well-formed — whether it should be trusted is a question for the server holding the key.