Are these developer tools free?
Yes. The full collection is free to use, with no account, no signup flow, and no pricing gate.
Developer Tools
The dev tools you
actually need.
Fast, focused tools for everyday development.
16 tools and growing.
GUID Generator
Generate RFC 4122 v4 UUIDs in bulk. Copy individually or all at once.
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Lorem Ipsum
Placeholder text by paragraphs, sentences, or words. Fully customisable.
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Case Converter
Convert to camelCase, snake_case, CAPS, Title Case, kebab-case, and more.
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JSON
JSON Formatter
Format, beautify, and minify JSON with syntax highlighting and error detection.
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JSON Validator
Validate JSON structure, pinpoint errors by line, and inspect parsed statistics.
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Encoding
Base64
Encode and decode Base64 strings instantly — handles Unicode text safely.
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URL Encode / Decode
Percent-encode or decode URLs and query parameters with one click.
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Tools
Timestamp Converter
Convert Unix timestamps to human-readable dates and back. Seconds or milliseconds.
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Regex Tester
Test regular expressions live. See all matches, groups, and positions highlighted.
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Hash Generator
Generate SHA-1, SHA-256, SHA-384, and SHA-512 hashes via the WebCrypto API.
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Security & Identity
Random String Generator
Generate cryptographically random strings — tokens, secrets, keys — with a custom character set.
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Password Generator
Strong random passwords with entropy scoring. Choose length, uppercase, symbols, and more.
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UUID Validator
Validate one or many UUIDs, detect version (v1–v5), variant, and formatting issues.
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JWT Decoder
Decode JWT tokens and inspect header, payload claims, and expiration status instantly.
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Font Generator
Convert text to bold, italic, cursive, monospace, bubble, and 20+ Unicode font styles. One-click copy.
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YAML ↔ JSON
Convert YAML to JSON or JSON to YAML instantly. Bidirectional, client-side, with adjustable indentation.
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Image
Free online developer tools for daily debugging, formatting, encoding, and validation
SimpleDevTools brings together the browser-based utilities developers reach for every day: a JSON formatter, JSON validator, UUID generator, regex tester, Base64 encoder, URL encoder, hash generator, timestamp converter, password generator, and more. Each tool is designed to open fast, solve one job well, and stay out of the way.
These tools are useful for API development, test-data generation, data cleanup, payload inspection, query-string debugging, security workflows, and common frontend or backend support tasks. Because the utilities are focused and client-side, they work well for quick checks during development without extra setup.
JSON Formatter
Beautify, minify, and inspect JSON payloads while debugging APIs and config files.
UUID Generator
Generate version 4 UUIDs and GUIDs for IDs, fixtures, and test data.
Regex Tester
Test regular expressions against sample text with live matches and groups.
Timestamp Converter
Convert Unix timestamps and ISO dates when tracing logs and backend events.
Common questions about these developer tools
Which tools are best for JSON and API debugging?
JSON Formatter, JSON Validator, Base64 Encoder, and URL Encode / Decode cover the most common payload, encoding, and query-string checks.
Can I use these tools for IDs, test data, and security workflows?
Yes. UUID Generator, Random String Generator, Password Generator, and Hash Generator are built for those everyday tasks.
Do the tools cover timestamps, text conversion, and regex testing too?
Yes. You can convert Unix timestamps, test regular expressions, and transform text casing without leaving the site.
100% client-side · Zero dependencies · Open forever