CSV to JSON Converter
Convert CSV, TSV, or delimited text to JSON locally in your browser for API mocks, imports, fixtures, and documentation.
Local-first developer workbench
Useful tools. No ceremony.
Format, inspect, compare, and generate without sending your input to a server.
18browser-based tools
Every utility runs locally unless its page explicitly says otherwise.
JSON & data
JSON & data
Open tool →
JSON Formatter
Format, validate, minify, and copy JSON locally in your browser without sending input to a server.
JSON Pointer Resolver
Resolve RFC 6901 JSON Pointers against JSON locally in your browser for OpenAPI, JSON Schema, JSON Patch, and API debugging.
JSON Schema Generator
Generate a starter JSON Schema from example JSON locally in your browser for API contracts, validation, tests, and documentation.
JSON to TypeScript Types Generator
Generate TypeScript interfaces or type aliases from JSON locally in your browser for API responses, fixtures, and backend contracts.
JSONPath Tester
Test common JSONPath expressions against JSON locally in your browser for API debugging, fixtures, logs, and documentation.
Encode & inspect
Encode & inspect
Base64 Encoder / Decoder
Encode text to Base64 and decode Base64 back to readable text locally in your browser.
JWT Decoder
Decode JWT header and payload claims locally in your browser without uploading tokens or verifying signatures.
Unix Timestamp Converter
Convert Unix timestamps to UTC and local dates, or convert date strings to seconds and milliseconds locally in your browser.
URL Encoder / Decoder
Encode full URLs, encode query parameters, and decode percent-encoded URL strings locally in your browser.
Text & query
Text & query
Markdown Table Generator
Convert CSV, TSV, or pasted rows into Markdown tables locally in your browser for READMEs, API docs, technical notes, and reports.
Regex Tester
Test JavaScript regular expressions locally with flags, matches, capture groups, and replacement previews.
SQL Formatter
Format, minify, and copy SQL queries locally in your browser for easier backend debugging, code review, and documentation.
Text Diff Checker
Compare two text snippets locally in your browser with line-by-line differences for JSON, SQL, config files, logs, and API responses.
Reference & generate
Reference & generate
Big-O Cheat Sheet
Look up common Big-O complexities for Java collections, algorithms, and backend patterns with a fast browser-based reference table.
Cron Parser
Explain standard five-field cron expressions and preview upcoming run times locally in your browser.
HTTP Status Code Lookup
Search common HTTP status codes locally in your browser with REST API usage notes, retry guidance, and backend examples.
UUID Generator
Generate UUID v4 values locally in your browser for request IDs, idempotency keys, database records, and test data.
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