Web Developer Utilities
Fast, client-side tools for formatting code, testing regex, and converting data formats.
Quick browser-based utilities for common developer tasks — format a JSON payload, decode a JWT, convert between data formats, or test a regex against real input. These tools run entirely in your browser, which means API responses containing auth tokens, internal SQL queries, and proprietary configuration files stay on your device.
What these tools cover
- → JSON Formatter — Validate and beautify JSON payloads.
- → Base64 Encoder — Encode and decode strings or files to Base64.
- → QR Code Gen — Generate customizable SVG/PNG QR codes.
- → Regex Tester — Test and debug regular expressions in real-time.
- → CSS Minifier — Minify and compile CSS styles.
- → LLM API Cost — Estimate token overhead for OpenAI, Claude, and Gemini.
- → String Formatter — Instantly convert text to camelCase, snake_case, PascalCase, or kebab-case.
- → JSON to CSV — Flatten and convert nested JSON objects into tabular CSV data.
- → Meta Tag Gen — Generate HTML meta tags, Twitter Cards, and Open Graph data.
- → UUID Generator — Instantly generate bulk v4 UUIDs / GUIDs.
- → JWT Decoder — Decode JSON Web Tokens securely without sending payloads.
- → HTML Entity Encoder — Safely encode and decode HTML entities to prevent XSS.
- → Markdown to HTML — Convert Markdown to clean HTML with live preview and XSS protection.
- → Text Diff Checker — Compare two text blocks or code snippets to find the exact differences.
- → Unix Timestamp — Convert Unix epoch times to human-readable dates and vice versa.
- → IP Subnet Calculator — Calculate network CIDR ranges, broadcast addresses, and usable hosts.
- → JSON to YAML — Instantly translate JSON configurations into clean, readable YAML.
- → URL Encoder/Decoder — Safely encode URLs for HTTP parameters or decode percent-encoded strings.
- → SQL Formatter — Instantly beautify messy SQL queries with perfect indentation.
JSON Formatter
Validate and beautify JSON payloads.
Base64 Encoder
Encode and decode strings or files to Base64.
QR Code Gen
Generate customizable SVG/PNG QR codes.
Regex Tester
Test and debug regular expressions in real-time.
CSS Minifier
Minify and compile CSS styles.
LLM API Cost
Estimate token overhead for OpenAI, Claude, and Gemini.
String Formatter
Instantly convert text to camelCase, snake_case, PascalCase, or kebab-case.
JSON to CSV
Flatten and convert nested JSON objects into tabular CSV data.
Meta Tag Gen
Generate HTML meta tags, Twitter Cards, and Open Graph data.
UUID Generator
Instantly generate bulk v4 UUIDs / GUIDs.
JWT Decoder
Decode JSON Web Tokens securely without sending payloads.
HTML Entity Encoder
Safely encode and decode HTML entities to prevent XSS.
Markdown to HTML
Convert Markdown to clean HTML with live preview and XSS protection.
Text Diff Checker
Compare two text blocks or code snippets to find the exact differences.
Unix Timestamp
Convert Unix epoch times to human-readable dates and vice versa.
IP Subnet Calculator
Calculate network CIDR ranges, broadcast addresses, and usable hosts.
JSON to YAML
Instantly translate JSON configurations into clean, readable YAML.
URL Encoder/Decoder
Safely encode URLs for HTTP parameters or decode percent-encoded strings.
SQL Formatter
Instantly beautify messy SQL queries with perfect indentation.
How to get accurate results
For regex, test against edge cases from your actual data, not just a clean sample — patterns that match the happy path often fail on real production input with unexpected encoding, special characters, or empty strings. For LLM API cost estimation, verify current token pricing on the provider's official pricing page before budgeting — model costs change with each release cycle. For subnet calculations, double-check CIDR notation — a single bit difference in the prefix changes the usable host count and broadcast address.
When to use these tools
- → Formatting a JSON API response for readability during a debugging session
- → Decoding a JWT to inspect its claims without pasting the token into a public service that may log payloads
- → Testing a regex pattern against sample input before committing the implementation to code
- → Converting a JSON API response to CSV to prepare data for a spreadsheet or database import
- → Estimating LLM token costs before choosing a model for a production feature at scale
Frequently Asked Questions
What developer tools are available?
JSON formatter, JSON to CSV, JSON to YAML, regex tester, CSS minifier, SQL formatter, string formatter, URL encoder, Base64 encoder, UUID generator, JWT decoder, Markdown to HTML, HTML entity encoder, Unix timestamp converter, bcrypt generator, network subnet calculator, diff checker, LLM API cost estimator, and meta tag generator.
Do these tools work with sensitive code?
Yes — every tool runs client-side in your browser. No code, queries, tokens, or IP addresses are ever sent to a server.
Are there usage limits?
No limits of any kind — no rate limiting, no character caps, no account required.
Can I use these tools offline?
Yes. After the page loads, all processing is local. You can disconnect from the internet and every tool continues to function.