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Online Developer Tools & Utilities
Use free developer tools for JSON formatting, regex testing, code cleanup, encoding helpers, cron building, and browser-based debugging tasks.
All tools in this category
24 toolsBrowse the full category directory with consistent tool cards and clear descriptions.
Code Snippet Formatting Tool
Clean indentation, blank lines, and pasted code before you share it.
JSON Diff Tool
Compare two JSON documents, isolate changed paths quickly, and review structural differences without manually scanning formatted blocks.
JSON Formatter and Validator: JSONPath and Diff
Format, validate, diff, and inspect JSON in a browser-based workspace with JSONPath, schema checks, repair hints, and no uploads.
JSON Minifier
Turn formatted JSON into compact output fast, keep the payload local, and confirm it still parses before you copy or export it.
JSON Schema Validator
Check a JSON payload against a schema, surface failing paths quickly, and keep contract checks local while you iterate.
JSON to XML Converter
Convert JSON into XML markup, choose sensible root and item tags, and keep the whole transformation inside your browser.
Base64 + Hashing Tool
Encode and decode Base64, create hashes, and compare outputs locally before you reuse text, payloads, or checksums.
Cron Expression Builder
Compose, validate, and preview standard 5-field cron schedules before you deploy jobs or change automation timing.
CSV to JSON Converter
Paste CSV from a spreadsheet, detect the delimiter automatically, and generate clean JSON objects in one browser-based step.
HEIC to JPG: iPhone Photos, Browser-Based
Turn Apple HEIC and HEIF images into shareable JPG files locally in your browser without sending photos to a server.
JSON to CSV Converter
Turn structured JSON into spreadsheet-ready CSV, choose a delimiter, and flatten nested objects when needed in one browser-based workflow.
JSON Validator: Syntax, Format and Minify
Check whether JSON is valid, jump to the exact syntax error, repair common issues, and format or minify the same payload locally.
JWT Decoder & Validator
Decode JWT structure, inspect claims, and validate expiry, issuer, and audience rules with no server upload.
Lorem Ipsum Generator
Generate deterministic placeholder copy for mockups, wireframes, QA, and draft content workflows.
Markdown Preview Tool
Preview Markdown output while you write so you can catch heading, table, link, and code-block issues before publishing.
PDF Metadata Remover
Strip standard PDF document-info metadata locally, review what was cleared, and download a cleaner file before sharing.
Regex Cheat Sheet
Browse common JavaScript regex tokens, group types, flags, and examples without leaving the browser.
Regex Explain Tool
Break a JavaScript regex into readable parts, inspect group and quantifier structure, and preview the pattern on sample text locally.
Regex Generator
Generate JavaScript regex starters for common validation and search patterns, then test them against sample input locally.
Regex Replace Tool
Apply JavaScript regex replacements locally, inspect which matches were changed, and keep source text out of external services.
Regex Tester: Patterns, Flags and Matches
Debug JavaScript regex with live matches, capture groups, test cases, and replacement previews in a browser-based workspace.
Timestamp Converter: Unix, ISO and Local
Translate between Unix seconds, Unix milliseconds, UTC, and local date-time formats without leaving the browser.
URL Encoder and Decoder: Percent Encoding
Switch between encoding and decoding, choose component-safe mode, and inspect the converted URL text before reuse.
UUID Generator: v4, v1 and Bulk
Create random UUID v4 values in standard, uppercase, compact, or brace-wrapped formats without leaving the browser.