Developer Tools

59 tools 100% Client-Side

Formatters, validators, regex engines, database diagrammers, and dev utilities.

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Developer59 tools

Formatters, validators, regex engines, database diagrammers, and dev utilities.

100% Local Only

Showing 59 tools

Local

JSON Formatter & Validator

Format, beautify, validate, and minify JSON with interactive collapsible tree explorer, line-number error markers, and JSON5 relaxed syntax support.

developer

Local

YAML Formatter & Validator

Format and validate YAML streams with multi-document support (---), tab indentation warning fixers, block/flow formatting, and YAML to JSON conversion.

developer

Local

Base64 Encoder & Decoder

Encode and decode UTF-8 Unicode text, files, images, and Data URLs with URL-safe Base64 toggles, line wrapping, and live image preview thumbnails.

developer

Local

JWT Decoder & Inspector

Base64URL decode JWT tokens, inspect registered and custom claims (exp, iat, iss, sub), detect security vulnerabilities, and verify HMAC signatures.

developer

Local

UUID Generator & Validator

Generate v4 random, v7 time-ordered sortable, and v1 timestamp UUIDs with bulk generation up to 5,000 items, custom formatting, and structural validation.

developer

Local

Cron Expression Tester & Debugger

Validate, debug, and simulate cron schedules with field-by-field error diagnostics, upcoming execution timelines, moment checkers, and DST edge-case alerts.

developer

Local

Unix Timestamp Converter

Convert between Unix epoch timestamps and human dates with auto-unit detection (s, ms, μs, ns), live ticking clock, multi-timezone comparisons, and date math.

developer

Local

Regex Tester & Debugger

Live regex tester with all JS flags (g, i, m, s, u, y), dual-layer match highlighting, capture group inspectors, substitution replace, and cheat sheets.

developer

Local

SQL Formatter & Beautifier

Format and beautify SQL across PostgreSQL, MySQL, T-SQL, SQLite, BigQuery, Snowflake, and Oracle with customizable casing, comma style, and minify mode.

developer

Local

Markdown Editor & Studio

Full-featured Markdown editor with live split preview, GFM tables, KaTeX LaTeX math, Mermaid diagrams, syntax highlighting, and PDF export.

developer

Local

Neural Network Visualizer & ML Studio

Interactive client-side machine learning playground. Draw shapes or digits on canvas, train an MLP in real time, and visualize live synaptic weights, activations, and loss curves.

developer

Local

Hash & HMAC Generator

Generate SHA-256, SHA-512, SHA-384, SHA-1, MD5, CRC32 hashes and HMAC signatures with secret keys and chunked file streaming for large files.

security

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