🛠️ Developer Tools

Formatters, converters, encoders and searchable references — the utilities that live next to your editor.

All developer tools

JSON Formatter

Beautify, validate and minify JSON with instant error messages.

Regex Tester

Live regex testing with match highlighting and capture groups.

Diff Checker

Compare two texts line by line with highlighted changes.

Cron Expression Generator

Build cron schedules and see them explained with next run times.

UUID Generator

Generate cryptographically secure UUID v4 identifiers in bulk.

Base64 Encoder / Decoder

Encode or decode Base64 with Unicode and URL-safe support.

Unix Timestamp Converter

Convert epoch timestamps to dates and back, in UTC and local time.

URL Encoder / Decoder

Percent-encode or decode URLs and query parameters.

JWT Decoder

Inspect a JWT's header, payload and expiry — fully client-side.

Hash Generator

SHA-1/256/384/512 hashes for text and files, computed locally.

Markdown Previewer

Live side-by-side Markdown editing with HTML export.

HTML Entity Encoder

Escape HTML to entities and decode them back.

Byte Size Converter

Convert bytes ⇄ KB/MB/GB/TB, decimal and binary units.

Image to Base64

Turn images into data URIs with HTML & CSS snippets.

JSON ⇄ CSV Converter

Convert JSON arrays to CSV and back, with proper quoting.

IP Subnet Calculator

Network, broadcast, host range and netmask from any CIDR.

llms.txt Generator

Create and validate llms.txt files for AI crawlers.

Number Base Converter

Binary ⇄ decimal ⇄ hex ⇄ octal, any base 2–36, exact.

Robots.txt Generator

Build a robots.txt — with one-click AI crawler blocking.

Meta Tag Generator

Title, description, Open Graph and Twitter Card tags.

AI Crawler Detector

Identify AI bots from user agents and access logs.

Security.txt Generator & Validator

Create and check an RFC 9116 security.txt file.

AI Search Readiness Checker

Audit pages for AI search, schema, robots and llms.txt.

Schema Markup Generator

Generate JSON-LD for Article, FAQ, local business and app pages.

AI Content Access Policy Generator

Create robots.txt, llms.txt and AI crawler access policy snippets.

Prompt Injection Scanner

Find hidden AI instructions and suspicious prompt text.

AI Citation Snippet Generator

Create concise snippets that AI/search engines can cite.

GEO Content Brief Generator

Plan AI-search-ready pages with entities, FAQs and schema notes.

AI Bot Blocker Rules Generator

Generate .htaccess, Nginx and Cloudflare rules for AI bots.

CSV to JSON

CSV ⇄ objects: quoted fields, headers, any delimiter.

XML Formatter

Pretty-print, minify and validate XML.

CSS Minifier

Compress CSS for production or expand it for reading.

SQL Formatter

Uppercase keywords, one clause per line, clean indent.

JSON ⇄ YAML

Convert config files between JSON and YAML.

Checksum Calculator

CRC32 and Adler-32 checksums of any text.

HTTP Status Codes

Searchable reference for every HTTP status code.

CSS Clamp Calculator

Generate fluid CSS clamp() formulas for type and spacing.

Color Palette Generator

Create tints, shades and CSS variables from one color.

UTM Builder

Create campaign tracking URLs with UTM parameters.

Random Color Generator

Random colors in hex, RGB or HSL with swatches.

HTML Minifier

Strip comments and whitespace from HTML, safely.

Hex Dump Viewer

Classic hex dump of any text's UTF-8 bytes.

JSON Escape

Escape or unescape JSON string literals.

Chmod Calculator

rwx checkboxes ⇄ octal 755 ⇄ rwxr-xr-x notation.

Password Strength Checker

Entropy, crack time and weaknesses — checked locally.

Fake Data Generator

Fake users with names, emails and cities as JSON or CSV.

Luhn Checker

Validate Luhn checksums (cards, IMEI) with working shown.

Regex Cheat Sheet

Searchable regex reference: tokens, examples, flags.

ASCII Table

All 128 ASCII codes with hex, decimal, octal, binary.

Git Cheat Sheet

Searchable Git commands: commit, branch, rebase, undo.

Common Ports

Searchable TCP/UDP port reference: SSH, HTTPS, databases.

About these tools

Format and validate JSON, SQL, XML and CSS; convert between CSV, JSON and YAML; encode, decode, hash and checksum anything; and keep the references you always end up googling — HTTP status codes, common ports, Git commands, regex tokens, the ASCII table — one search box away. Every tool runs entirely in your browser, so pasting proprietary code or production data is safe: nothing is uploaded, logged or stored.

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