9kit.org
Developer Tools

Developer Utilities

Essential coding tools for developers. Format, encode, decode, and generate hashes — all 100% private, running directly in your browser.

JSON Formatter & Validator

Format, validate, and beautify JSON data instantly

Open tool

JSON to CSV

Convert JSON data to CSV format

Open tool

JSON to TypeScript

Generate TypeScript interfaces from JSON

Open tool

JSON Diff

Compare two JSON objects and highlight differences at field level

Open tool

JSON to SQL Converter

Convert JSON arrays to SQL INSERT statements with CREATE TABLE definition

Open tool

JSONPath Tester

Test and evaluate JSONPath expressions

Open tool

YAML Formatter & Validator

Format, validate, and prettify YAML with error details

Open tool

YAML to JSON

Convert between YAML and JSON formats

Open tool

TOML ↔ JSON Converter

Convert between TOML and JSON configuration formats

Open tool

TOML ↔ YAML Converter

Convert between TOML and YAML configuration formats

Open tool

XML Formatter

Format and validate XML documents

Open tool

XPath Tester

Test XPath expressions against XML/HTML

Open tool

GraphQL Formatter

Format and beautify GraphQL queries, mutations, and SDL

Open tool

SQL Formatter

Format, minify, and beautify SQL queries

Open tool

SQL to JSON Converter

Parse SQL INSERT statements and convert to JSON array

Open tool

Base64 Encoder

Encode and decode Base64 text and files

Open tool

Base32/Base58/Base85 Encoder

Encode and decode Base32, Base58, and Base85 format text

Open tool

URL Encode/Decode

Encode or decode URL strings with component-only option

Open tool

URL Parser

Parse and analyze URL components

Open tool

Hash Generator

Generate MD5, SHA-1, SHA-256, SHA-512 hashes

Open tool

Advanced Hash Generator

Generate hashes with SHA3, RIPEMD160, CRC32, xxHash and more

Open tool

HMAC Generator

Generate HMAC signatures with SHA algorithms

Open tool

Hex Encoder/Decoder

Encode text to hex or decode hex to text with multiple format options

Open tool

HTML Encoder

Encode and decode HTML entities

Open tool

Regex Tester

Test regular expressions with live preview

Open tool

Regex Cheatsheet

Interactive regex syntax quick reference with examples

Open tool

Text Diff / Code Diff

Compare two texts and highlight differences (added, removed, modified lines)

Open tool

Text Escape/Unescape Converter

Escape or unescape text sequences for programming

Open tool

JavaScript Minifier

Minify JavaScript code by removing whitespace and comments

Open tool

CSS Minifier

Minify CSS code by removing whitespace and optimizing values

Open tool

HTML Minifier

Minify HTML by removing whitespace, comments, and optional tags

Open tool

TypeScript to JavaScript Transpiler

Convert TypeScript/TSX code to JavaScript in the browser

Open tool

Markdown to HTML

Convert Markdown syntax to HTML

Open tool

JWT Decoder

Decode JSON Web Tokens to view header and payload

Open tool

JWT Encoder & Signer

Encode and sign JWT tokens with HMAC algorithms

Open tool

Bcrypt Hash Generator & Verifier

Generate and verify bcrypt password hashes with adjustable cost factor

Open tool

Password Strength Analyzer

Analyze password strength using zxcvbn algorithm

Open tool

AES Encryption / Decryption

Encrypt and decrypt text using AES-256-GCM encryption

Open tool

RSA Key Pair Generator

Generate RSA public/private key pairs in PEM format

Open tool

HTTP Request Builder & Tester

Build and test HTTP requests with custom headers, body, and authentication

Open tool

HTTP Status Codes Reference

Complete HTTP status code reference with descriptions, RFC links, and usage examples

Open tool

cURL Command Generator

Generate cURL commands from HTTP request parameters

Open tool

CORS Checker

Check CORS configuration and analyze preflight requests

Open tool

WebSocket Tester

Test WebSocket connections with message sending and receiving

Open tool

DNS Lookup

Query DNS records using DNS-over-HTTPS

Open tool

IP Lookup

Query IP address geolocation, ISP, and ASN information

Open tool

UUID Generator

Generate random UUIDs and GUIDs

Open tool

UUID Validator

Validate UUID format and generate random UUIDs

Open tool

UUID / NanoID / ULID Generator

Generate UUID, NanoID, and ULID unique identifiers

Open tool

Slug Generator

Generate URL-friendly slugs from text

Open tool

Number Base Converter

Convert numbers between binary, decimal, hex and other bases

Open tool

Timestamp Converter

Convert between Unix timestamps and dates

Open tool

CRC32 / Checksum Generator

Calculate CRC32, CRC32C and Adler32 checksums

Open tool

MIME Checker

Check and validate MIME types

Open tool

User Agent Parser

Parse user agent strings to identify browsers and OS

Open tool

Cron Parser

Parse and validate cron job expressions

Open tool

CIDR Calculator

Calculate network ranges and subnet masks

Open tool

Chmod Calculator

Calculate Linux file permissions in numeric and symbolic notation

Open tool

ASCII / Unicode Lookup

Look up ASCII and Unicode characters, find character codes, HTML entities, CSS escapes

Open tool

Git Cheatsheet

Common Git commands quick reference with examples

Open tool