body{background:#1e1e1e;color:#e0e0e0;font-family:system-ui,sans-serif;padding:20px;max-width:800px;margin:0 auto}h1{color:#9cdcfe}h2{color:#4ec9b0;margin-top:24px}ul{padding-left:20px}li{margin:6px 0}a{color:#569cd6}DevToolKit — Free Online Developer Tools54+ free tools for developers, network engineers, and DevOps professionals. All tools run in your browser — no sign-up, no data storage. Please enable JavaScript to use the interactive tools.Developer Tools

JSON Formatter & Validator — Format, validate, and beautify JSON data

Base64 Encoder & Decoder — Encode and decode Base64 strings

URL Encoder & Decoder — Encode and decode URL components

JWT Decoder — Decode and inspect JSON Web Tokens

Regex Tester — Test regular expressions with live matching

UUID Generator — Generate UUIDs v1, v4, v5

Hash Generator — Generate MD5, SHA-1, SHA-256, SHA-512 hashes

Password Generator — Generate strong random passwords

Color Picker & Converter — Convert HEX, RGB, HSL colors

Subnet Calculator — Calculate IP subnets and CIDR notation

Cron Expression Parser — Parse cron expressions with next run times

Chmod Calculator — Calculate Unix file permissions

Unix Timestamp Converter — Convert timestamps to dates

YAML ↔ JSON Converter — Convert between YAML and JSON

CSV ↔ JSON Converter — Convert CSV to JSON and back

Diff Checker — Compare two texts and find differences

SQL Formatter — Format and beautify SQL queries

Markdown Preview — Preview Markdown with live rendering

HTML Entity Encoder — Encode and decode HTML entities

Lorem Ipsum Generator — Generate placeholder text

Network & DevOps Tools

DNS Lookup — Query DNS records for any domain

SSL/TLS Checker — Check SSL certificate validity and grade

IP Geolocation Lookup — Find IP address location and ISP

WHOIS Lookup — Domain registration details

HTTP Header Checker — Inspect response and security headers

Port Scanner — Scan open TCP ports

Ping Tool — Check host availability and latency

Generators & Validators

.htaccess Generator — Apache redirect and rewrite rules

Robots.txt Generator — Generate crawler rules

Meta Tag Generator — SEO, Open Graph, Twitter Cards

IBAN Validator — Validate bank account numbers

Blog Articles

Mastering Zero-Downtime Deployments with Terraform

Prompt Stuffing Is Killing Your Agent

Securing Production Debugging in Kubernetes

LLMs on Kubernetes: Understanding the Threat Model

Serverless ETL/ELT Architecture with AWS

Browse all 54 tools | Developer Blog | About | Privacy Policy