A fast, private toolbox for everyday developer work.

13 tools for inspecting and converting the data you work with. Open one, paste your input, get the answer. No account, no upload, no waiting.

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JSON Formatter & ValidatorPaste JSON to validate it and format it. Syntax errors are reported with the exact line and column.
JWT DecoderPaste a JSON Web Token to read its header and claims. Expiry times are shown as real dates, and unsigned tokens are called out.
Base64 Encoder & DecoderEncode text to Base64, or decode Base64 back to text. Handles UTF-8 correctly, offers base64url, and tells you when the result is binary rather than pretending it is text.
Unix Timestamp ConverterConvert a Unix timestamp to a readable date, or a date to a Unix timestamp. Detects whether a value is in seconds, milliseconds, microseconds or nanoseconds, and refuses to guess when a date is ambiguous.
UUID & ULID GeneratorGenerate UUIDs and ULIDs in your browser. v4 for random, v7 or ULID when you need them to sort by time, with the trade-offs explained rather than assumed.
URL Encoder & DecoderEncode and decode percent-escapes with the right scheme. Shows what stays unescaped in each, handles UTF-8 correctly, and flags anything it could not read exactly.
Regex TesterTest a JavaScript regular expression against your own text. Every match with its offset and capture groups, a replace preview, and the browser's own error message.
Hash GeneratorHash text with SHA-256, SHA-384, SHA-512, SHA-1 or CRC-32. Reads the input as UTF-8 text or as raw hex bytes, because those give different answers and that is where mismatches come from.
Text DiffCompare two texts line by line, with word-level detail on the lines that changed. Sees through line-ending and whitespace differences, and tells you when a diff is too large to be exact rather than pretending otherwise.
Cron Expression BuilderBuild a cron expression and see the next times it fires, in any time zone. Flags the two cases that silently do the wrong thing: a time that does not exist on a daylight-saving day, and one that happens twice.
YAML to JSON ConverterConvert YAML to JSON, or JSON to YAML. Names the schema it used, and reports every value the conversion changed, dropped or rounded — including the ones a YAML 1.1 parser would read differently.
SQL FormatterReformat a SQL query: one clause per line, consistent keyword case, short lists kept inline. Never changes your query, and never claims your SQL is valid.
JSONPath TesterTest JSONPath expressions against your JSON and see matching values instantly.

All tools

Grouped by what you are trying to do, not by implementation.

API & data

Inspect the payloads moving through your API.

Text & patterns

Search, match and compare text.

Conversion

Move data between encodings and formats.

Scheduling

Work with dates, times and cron schedules.

Database & code

Format queries and code you are writing.

SQL FormatterReformat a SQL query: one clause per line, consistent keyword case, short lists kept inline. Never changes your query, and never claims your SQL is valid.