codinganthem Free Online Developer Utilities & Tools

47 developer tools that never phone home. Paste JSON from ChatGPT, decode a JWT from a bug report, or format SQL from Copilot — instantly, with nothing ever leaving this tab.

Tools

47 of 47

Base64 Encoder / Decoder

Encode and decode text or files to and from Base64

Encoders

Case Converter

Convert text between camelCase, snake_case, PascalCase, and more

Text Utils

Color Contrast Checker

Check WCAG contrast ratio between two colors for accessibility

Converters

Color Converter

Convert colors between HEX, RGB, and HSL formats

Converters

Cron Expression Parser

Decode cron expressions into plain-English schedules

Converters

CSS Formatter

Format and beautify CSS with proper indentation

Formatters

CSV to JSON

Convert CSV data to a JSON array instantly

Converters

cURL to Fetch

Convert a cURL command into a JavaScript fetch() call

Web

Hash Generator

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

Security

HTML Entities Encoder / Decoder

Encode and decode HTML entities like &lt; and &gt;

Web

HTML Formatter

Format and beautify HTML markup with proper indentation

Formatters

Image to Base64

Convert any image to a Base64 data URL instantly

Encoders

JavaScript Formatter

Format and beautify JavaScript code with proper indentation

Formatters

JSON Diff

Compare two JSON documents and highlight every addition, removal, and change

Formatters

JSON Formatter

Format, validate, and minify JSON instantly

Formatters

JSON Statistics

Analyze JSON structure — node count, depth, type distribution, and size

Formatters

JSON to CSV

Convert a JSON array to CSV format

Converters

JSON to TypeScript

Generate TypeScript interfaces from a JSON object

Converters

JSON to YAML

Convert JSON to YAML format instantly

Converters

JWT Decoder

Decode and inspect JWT tokens — header, payload, and signature

Security

JWT Generator

Create signed JWT tokens with HS256, HS384, or HS512 using WebCrypto

Security

JWT Validator

Verify a JWT token's signature and check its expiry

Security

Lorem Ipsum Generator

Generate placeholder lorem ipsum text for designs and mockups

Generators

Markdown Previewer

Write Markdown and see a live rendered HTML preview

Visualizers

Mermaid Diagram Viewer

Render Mermaid diagrams from code — flowcharts, sequence, ER, and more

Visualizers

Mock Data Generator

Generate realistic fake data for testing — names, emails, addresses, and more

Generators

Number Base Converter

Convert numbers between binary, octal, decimal, and hexadecimal

Converters

Password Generator

Generate strong, random passwords with custom rules

Security

Prompt Template Filler

Fill in {{variables}} in a prompt template and get the resolved text instantly

QR Code Generator

Generate a QR code for any text or URL instantly

Generators

Regex Tester

Test regular expressions with live match highlighting

Text Utils

Slug Generator

Convert any text into a URL-friendly slug

Web

SQL Formatter

Format and beautify SQL queries with dialect-aware indentation

Formatters

SQL IN Generator

Turn a list of values into a SQL IN clause

Converters

String Escape / Unescape

Escape or unescape special characters in strings

Encoders

Text Diff

Compare two texts and highlight the differences

Text Utils

Token Counter & Estimator

Count tokens and estimate API cost for GPT, Claude, and Gemini models

TOTP / OTP Generator

Generate time-based one-time passwords (TOTP) from a secret key

Security

Unix Timestamp Converter

Convert Unix timestamps to human dates and back

Converters

URL Encoder / Decoder

Encode and decode URLs and query string parameters

Web

URL Parser

Break a URL into its components — protocol, host, path, query params, and hash

Web

User-Agent Parser

Parse a User-Agent string into browser, OS, and device details

Web

UUID Generator

Generate one or multiple UUIDs (v4) instantly

Generators

Word Counter

Count words, characters, sentences, and estimate reading time

Text Utils

XML Formatter

Format, validate, and beautify XML markup with proper indentation

Formatters

XML to JSON

Convert XML markup to a JSON object instantly

Converters

YAML to JSON

Convert YAML configuration to JSON format instantly

Converters

🔒

Your data stays local

No backend. No uploads. Everything runs in your browser — your JSON, passwords, and hashes never touch a server.

⚡

Results as you type

No submit buttons. No spinners. Tools respond on every keystroke — format JSON, match regex, compute hashes instantly.

∅

No account. Ever.

Open the URL, use the tool, close the tab. Free forever. No sign-up, no paywalls, no tracking.

🤖

Pairs well with AI

Paste ChatGPT or Copilot output straight into any tool. Validate JSON, encode Base64, or test regex without breaking your flow.

Frequently asked questions

Is my data safe when I use these tools?+

Yes. Every tool runs entirely in your browser using JavaScript and the Web Crypto API. Nothing you paste, type, or upload is ever sent to a server.

Do I need to create an account or sign up?+

No. All tools are free to use immediately — no sign-up, no login, no email required.

Are the tools actually free, or is there a paid tier?+

Completely free, with no paywalls or premium features. CodingAnthem is free forever.

How many tools does CodingAnthem offer?+

47 tools across formatters, encoders, generators, converters, security, and more — all free, all instant.

Can I use CodingAnthem alongside AI tools like ChatGPT or GitHub Copilot?+

Yes. Paste JSON, JWTs, SQL, or any AI-generated output directly into a tool to validate, format, or convert it — nothing leaves your browser in the process.