Curated tool collection
Developer Tools
Fast browser-based helpers for debugging payloads, cleaning data, and validating time-sensitive values.
51
focused tools
Frontend engineers, indie hackers, support teams, and technical marketers.
Tools
Pick a tool
JSON Formatter
Open →Format, validate, and minify JSON in your browser.
JWT Decoder
Open →Inspect JWT headers and payloads without leaving the page.
Base64 Studio
Open →Encode and decode Base64 text with one compact utility.
Unix Timestamp Converter
Open →Convert Unix timestamps to readable dates and back again.
CSV JSON Converter
Open →Convert simple CSV tables to JSON and JSON arrays back to CSV.
URL Encoder Decoder
Open →Encode URLs and query strings or decode them back to readable text.
HTML Entity Encoder
Open →Encode HTML entities or decode escaped markup back to readable characters.
Regex Tester
Open →Test regular expressions against sample text and inspect matches.
Browser Info
Open →See your browser, platform, language, viewport, and timezone details.
UUID Generator
Open →Generate fresh UUIDs instantly in the browser.
Password Generator
Open →Generate strong passwords with configurable character sets.
JSON Diff Checker
Open →Compare two JSON payloads and inspect changed keys quickly.
JSON Escape Unescape
Open →Escape JSON-safe strings or turn escaped text back into readable content.
JSON to TypeScript Interface
Open →Generate a basic TypeScript interface from JSON data.
HTTP Status Lookup
Open →Look up common HTTP response codes and understand what they mean fast.
User Agent Parser
Open →Parse user agent strings into browser, platform, and device details.
JSON Viewer
Open →View JSON structure, paths, and formatted output in one clean browser tool.
Hash Generator
Open →Generate SHA hashes for text instantly in the browser.
UUID Batch Generator
Open →Generate batches of UUIDs instantly for testing, seeding, and sample data.
JSON Schema Viewer
Open →Turn sample JSON into a readable schema-style view for faster handoff.
URL Parser
Open →Break a URL into origin, path, hash, and query parameters instantly.
Cron Expression Builder
Open →Preview and explain 5-part cron expressions without leaving the browser.
HTTP Header Viewer
Open →Parse raw HTTP headers into a cleaner key-value list for faster debugging.
JWT Expiry Checker
Open →Decode a JWT exp claim and see whether the token is still active.
SQL Formatter
Open →Format SQL into a cleaner readable shape for faster review and sharing.
HTML Table Generator
Open →Turn simple comma-separated rows into a clean HTML table instantly.
SVG to CSS Background
Open →Convert an SVG snippet into a CSS background-image data URL.
CSS Clamp Generator
Open →Generate fluid clamp values for responsive typography and spacing.
Email Obfuscator
Open →Obfuscate email addresses into HTML entities and mailto links.
Webhook Payload Viewer
Open →Inspect webhook JSON payloads in a cleaner key, type, and preview layout.
CSV Column Extractor
Open →Extract one column from a CSV block into a clean newline list.
CSS Grid Generator
Open →Generate clean CSS grid snippets for responsive card and layout systems.
Regex Replace Tester
Open →Test search-and-replace regex patterns and preview the output instantly.
CSV Row Counter
Open →Count total rows, data rows, and columns from a CSV block instantly.
Query String Builder
Open →Build URLs with clean query parameters without editing the string by hand.
Date Difference Calculator
Open →Calculate the day and week difference between two dates instantly.
UUID Validator
Open →Check whether a UUID is valid and normalize it for safer reuse.
Text List Sorter
Open →Sort text lists ascending or descending and optionally remove duplicates.
HTML Entity Decoder Pro
Open →Decode common named, numeric, and hex HTML entities into readable text.
Text Case Converter Pro
Open →Convert text into multiple naming and casing formats in one place.
Email Signature Preview
Open →Build a lightweight HTML email signature and preview it instantly.
YAML Viewer
Open →Turn JSON into a clean YAML-style view for faster reading and handoff.
Number List Deduplicator
Open →Deduplicate number lists and optionally sort them for easier reuse.
Markdown Table Generator
Open →Turn simple rows into a clean Markdown table instantly.
UUID List Formatter
Open →Clean and reformat UUID lists for code, docs, and data workflows.
Color Contrast Checker
Open →Check contrast ratios and WCAG pass states between two colors.
CSV Header Extractor
Open →Pull header names from a CSV block into a clean list instantly.
Meta Refresh Generator
Open →Generate a meta refresh tag for timed redirects and fallback page flows.
CSV Sample Generator
Open →Generate sample CSV rows from a header list in one step.
Line Number Adder
Open →Prefix each line of text with configurable line numbers.
Whitespace Cleaner
Open →Clean tabs, extra spaces, and repeated blank lines from messy text.
Quality promise
Each utility solves one focused task. We show what it accepts, what it returns, and where its result needs independent checking. Ordinary inputs stay in your browser whenever the workflow allows it.
Guides
Common JSON Errors and How to Fix Them
Learn why JSON parsing fails, how to identify the broken character, and how to correct common syntax mistakes safely.
JWT Decoding vs Signature Verification
Understand what a JWT decoder can reveal, what signature verification proves, and which claims applications must validate.
Regex Groups, Captures, and Replacements
A practical guide to grouping regular expressions, reusing captured text, and avoiding common replacement mistakes.