DevPane
Free developer tools that don't suck.
Twenty-nine precision tools for timestamps, encoding, formatting, testing, hashing, and more.
No accounts. No tracking. Just tools.
Developer Tools
Calculate
8/8Timestamps, subnets, colors, permissions, and number systems
Epoch Converter
Convert Unix timestamps to human-readable dates and vice versa
Cron Builder
Visual cron expression builder with natural language
Subnet Calculator
Calculate subnets, plan VPCs, and detect overlapping CIDRs
Color Converter
Convert colors between HEX, RGB, HSL, OKLCH with contrast checker
chmod Calculator
Calculate Unix file permissions with interactive grid and umask
Base Converter
Convert between binary, octal, decimal, hex, and custom bases
Byte Calculator
Convert between bytes, KB, MB, GB with SI and IEC units
Timezone Converter
Convert times across timezones with meeting planner
Encode & Decode
6/6Base64, URL, HTML entities, and hex conversions
Base64 Encoder
Encode and decode Base64 with file, URL-safe, and bulk modes
URL Encoder
Encode, decode, and parse URLs with query string builder
HTML Entities
Encode and decode HTML entities with XSS prevention and Unicode explorer
Hex Encoder
Convert between text and hex strings with hex dump view
Text Transform
Convert case, generate slugs, count words, and encode strings
Image to Base64
Convert images to Base64 data URIs and decode them back
Format & Validate
6/6JSON, YAML, SQL, Markdown, and Mermaid diagram formatting
JSON Formatter
Format, validate, and beautify JSON data
YAML Validator
Validate, format, and convert YAML with Kubernetes and GitHub Actions awareness
SQL Formatter
Format and beautify SQL with multi-dialect support and query analysis
Markdown Preview
Live Markdown editor with GFM support, HTML export, and table generator
Mermaid Diagram Renderer
Write Mermaid code, see live diagrams — flowcharts, sequences, ER, and more
ASCII to SVG
Turn ASCII art diagrams into beautiful SVG and PNG images
Inspect & Analyze
7/7JWT, regex, diff, HTTP status codes, and user agents
JWT Decoder
Decode and inspect JSON Web Tokens
Regex Tester
Test regular expressions with live matching and plain-English explanations
Diff Checker
Compare text and code with syntax-aware side-by-side diff
HTTP Status Codes
Interactive HTTP status code explorer with decision tree
CSV Viewer
Open, sort, filter, and analyze CSV and TSV files in a fast data grid
User Agent Parser
Parse and analyze browser user agent strings
API Playground
Test REST APIs, import curl commands, and generate code in 7 languages
Generate
8/8Hashes, UUIDs, passwords, and mock data
Hash Generator
Generate and verify MD5, SHA-1, SHA-256, and other hashes
UUID Generator
Generate, validate, and inspect UUIDs v1, v4, and v7
Password Generator
Generate secure passwords, passphrases, API keys, and encryption keys
Mock Data Generator
Generate realistic test data with visual schema builder
QR Code Generator
Generate and read QR codes for URLs, WiFi, vCards, and more
Schema Designer
Design database schemas visually and generate DDL for 4 SQL dialects
Architecture Diagram
Build cloud architecture diagrams with drag-and-drop nodes for AWS, GCP, Azure
Claude Code Agent Builder
Build and validate Claude Code sub-agent and slash-command files with a live preview
Lookup
3/3Domain intelligence, IP geolocation, and character references
What's New
Mermaid Timeline Diagrams launched — New interactive guide with 7 live-editable timeline examples — product releases, incident responses, sprint retros, and more. Edit the code, see the diagram update instantly.
JSON Spec Compliance Checker launched — Paste JSON and see exactly which RFC 8259 rules it violates — double quotes, trailing commas, comments, unquoted keys — with spec section citations and auto-fix.
JWT Security Analyzer launched — Paste a JWT into the best practices guide and get an instant A-F security grade with a reactive checklist showing which practices your token follows.
User Agent Parser launched — Parse and analyze browser user agent strings. Detect bots, inspect Client Hints API, and explore presets for common browsers, crawlers, and CLI tools.
ASCII / Unicode Table launched — Interactive ASCII and Unicode character reference with search, filtering by category, codepoint lookup, and bulk conversion tools.
IP Address Lookup launched — Look up any IP address: geolocation, reverse DNS, classification (public/private/reserved), format conversion, and WebRTC VPN leak testing.
Mock Data Generator launched — Generate realistic test data with a visual schema builder. 37 field types, bulk generation up to 100K rows, and export to JSON, CSV, SQL, TypeScript, XML, and YAML.
Hex Encoder launched — Convert between text and hex with multiple separator styles. Features xxd-style hex dump, file magic byte detection, hex color parsing, and pattern search.
Timezone Converter launched — Convert times across timezones with a meeting planner. Includes DST guide, UTC offset reference, and timezone best practices for developers.
Byte Calculator launched — Convert between bytes, KB, MB, GB, TB with both SI (1000-based) and IEC (1024-based) units. Includes file size cheat sheet and bandwidth calculator.
Base Converter launched — Convert between binary, octal, decimal, hex, Base32, Base58, Base64 and custom bases. Includes bitwise operations, arithmetic in any base, and reference tables.
ASCII to SVG Converter launched — Turn ASCII art diagrams into beautiful SVG and PNG images. Supports boxes, arrows, diamonds, nested layouts, and themed rendering. Our second Premium tool.
Mermaid Diagram Renderer launched — Our first Premium tool. Write Mermaid code, see live diagrams with zoom and pan. Export as SVG or PNG. Supports flowcharts, sequence diagrams, ER diagrams, and more.
8 New Tools Announced launched — All 8 tools from Phase 11-12 are now live: Base Converter, Byte Calculator, Timezone Converter, Hex Encoder, Mock Data Generator, IP Lookup, ASCII Table, and User Agent Parser.
All 20 Tools Live launched — The original DevPane suite is complete. Password Generator and HTML Entity Encoder are now live.
HTML Entities launched — Encode and decode HTML entities with XSS prevention mode, 251-entity reference table, and Unicode explorer.
Password Generator launched — Generate secure passwords, Diceware passphrases, API keys, and encryption keys with strength analysis.
18 Tools Now Live launched — HTTP Status Codes and Markdown Preview join the suite. Tier 3 complete.
Markdown Preview launched — Live split-pane Markdown editor with GFM support, HTML export, table generator, cheat sheet, and frontmatter editor.
HTTP Status Codes launched — Interactive HTTP status code explorer with decision tree, code snippets for 6 frameworks, and detailed explanations.
SQL Formatter launched — Format, minify, and analyze SQL queries with multi-dialect support for PostgreSQL, MySQL, SQLite, T-SQL, BigQuery, and Redshift.
YAML Validator launched — Validate, format, and convert between YAML, JSON, and TOML with Kubernetes manifest and GitHub Actions workflow detection.
14 Tools Now Live launched — Four new Tier 2 tools join the suite. UUID Generator, Diff Checker, Color Converter, and chmod Calculator are live.
chmod Calculator launched — Calculate Unix file permissions with interactive grid, umask calculator, and common preset library.
Color Converter launched — Convert colors between HEX, RGB, HSL, and OKLCH with WCAG contrast checker and palette generator.
Diff Checker launched — Compare text and code with syntax-aware side-by-side and unified diff views.
UUID Generator launched — Generate, validate, and inspect UUIDs v1, v4, and v7 with bulk generation and collision analysis.
Hash Generator launched — Generate and verify MD5, SHA-1, SHA-256, SHA-512, and other hashes with file hashing support.
URL Encoder launched — Encode, decode, and parse URLs with query string builder and component breakdown.
Regex Tester launched — Test regular expressions with live matching, plain-English explanations, and common pattern library.
Base64 Encoder launched — Encode and decode Base64 with file support, URL-safe mode, and bulk operations.
10 Tools Now Live launched — Four new Tier 1 tools join the original six. Base64, Regex, URL, and Hash are live.
Domain Dashboard launched — DNS records, WHOIS data, SSL certificate analysis, security headers audit, and overall health scoring.
Subnet Calculator launched — CIDR calculator, VPC planner, subnet splitter, overlap detector, and interactive cheat sheet.
Epoch Converter launched — Convert timestamps in 9 languages
Cron Builder launched — Visual cron builder with natural language input, clock face visualization, and frequency analysis
JSON Formatter launched — JSON Formatter, validator, and analyzer with Monaco Editor, tree view, schema inference, and diff mode
JWT Decoder launched — JWT decoder and security inspector with signature verification, token comparison, and code generation
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100% free · No accounts · Client-side (your data never leaves your browser) · Open-source-friendly · Built by Bluminal Labs