Free Developer Tools Online

40 free developer tools — all run in your browser.

UtilDaily offers a curated collection of free developer tools online that run entirely in your browser. Whether you need to format a JSON API response, encode a string to Base64, generate a UUID for your database schema, build a cron expression for a scheduled job, or convert data between CSV and JSON, every tool works instantly without any installation, sign-up, or server-side processing.

All processing happens client-side using standard Web APIs — your code, API tokens, and configuration data never leave your device. This privacy-first approach makes UtilDaily safe for working with sensitive payloads like authentication tokens, environment variables, and private keys that you would never want to paste into a server-side tool. Verify it yourself: open your browser's DevTools Network tab while using any tool and no outbound data requests appear.

The free dev tools collection covers common developer workflows across formatting, encoding and decoding, hashing, data conversion, URL manipulation, and random value generation. Each tool is designed to do one thing well — paste your input, get your result, and move on. No account walls, no usage limits, and no ads blocking your workflow. Works on any device with a modern browser: Chrome, Firefox, Safari, or Edge.

All Developer Tools (40)

Popular

JSON Formatter & Validator

Format, validate, and minify JSON data instantly.

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Popular

Base64 Encoder & Decoder

Encode text to Base64, or decode Base64 back to plain text. Supports full UTF-8.

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Popular

UUID v4 Generator

Generate random UUIDs (v4) in bulk with one click.

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URL Encoder & Decoder

Encode or decode URL components and query strings.

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Popular

JSON to CSV Converter

Convert JSON arrays to CSV format with one click. Supports nested objects.

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Popular

Random Wheel Spinner

Spin the wheel to pick random winners from your list. Three modes, CSV import, history tracking.

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CSV to JSON Converter

Convert CSV files or pasted data to JSON arrays. Auto-detects headers and types.

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Random Number & Dice

Generate random numbers, flip a coin, or roll dice — all in one place.

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Random List Picker

Paste a list of items and pick random winners instantly. Perfect for raffles and giveaways.

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Hash Generator

Generate MD5, SHA-1, and SHA-256 hashes from any text using your browser's built-in crypto.

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Nickname Generator

Generate random nicknames, gamer tags, and fantasy names instantly.

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Favicon Generator

Create favicons from images, text, or emoji. Generate multiple sizes with live preview.

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Case Converter

Convert text between 7 case styles: sentence, lower, UPPER, Title, Capitalized, aLtErNaTiNg, InVeRsE.

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Text Cleaner

Remove duplicate lines, extra whitespace, line breaks, and unwanted characters with 7 cleaning modes.

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Text Transformer

Reverse text, repeat N times, sort lines alphabetically, and find/replace with 4 transformation modes.

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Plain Text Converter

Convert HTML to plain text, strip Markdown syntax, or extract text from RTF with 3 conversion modes.

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Word Cloud Generator

Generate beautiful word clouds from text with customizable colors, sizes, and layouts.

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Roman Numeral Converter

Convert between numbers and Roman numerals (I, V, X, L, C, D, M) with validation and date formatting.

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QR Code Generator

Generate QR codes from URLs, text, or email. Download as PNG.

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Password Generator

Generate secure passwords with crypto.getRandomValues(). Length slider, character sets, entropy strength meter.

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Temperature Converter

Convert temperatures between Celsius, Fahrenheit, Kelvin, and Rankine in real time.

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Lorem Ipsum Generator

Generate lorem ipsum placeholder text by paragraphs, sentences, or words.

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JWT Decoder

Decode and inspect JSON Web Tokens — view header, payload, and expiry status instantly.

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Password Strength Checker

Check how strong your password is with realistic crack-time estimates and improvement suggestions.

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Morse Code Converter

Translate text to Morse code and decode Morse to English instantly.

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KM to Miles Converter

Convert kilometers to miles and miles to km with a simple calculator.

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MM to Inches Converter

Convert millimeters to inches and inches to mm with precision.

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Random String Generator

Generate random strings with custom length and character sets.

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Barcode Generator

Generate Code 128 barcodes from any text and download as SVG. No sign-up required.

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Random Number Generator

Generate cryptographically random numbers in any range — dice, lottery, statistics, or any custom min/max.

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Random Word Generator

Generate random English words filtered by type (noun/verb/adjective/adverb), length, and starting letter.

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Username Generator

Generate creative usernames for gaming, social media, or professional profiles in 5 styles.

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Number to Words Converter

Convert numbers to English words in cardinal, ordinal, or check-writing format up to quadrillions.

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KG to LBS Converter

Convert kilograms to pounds and back instantly. See results in lbs, oz, and stones with a quick-reference table.

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JavaScript Minifier

Minify JavaScript by removing whitespace, comments, and unnecessary characters. Shows original vs. minified size and reduction percentage.

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New

Cooking Converter

Convert between cooking measurements: oz to ml, cups to grams, teaspoons, tablespoons, pints, and liters. Includes ingredient density selector for accurate cup-to-gram conversion.

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Speed Converter

Convert between speed units: knots, mph, km/h, meters per second, and feet per second. Includes Beaufort wind scale reference and common speed benchmarks.

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Area Converter

Convert between area units: square feet, square meters, acres, hectares, square yards, square miles, and square kilometers. Includes real estate size reference table.

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Liquid Volume Converter

Convert between liquid volume units: US/UK gallons, liters, fluid ounces, cups, pints, and quarts. Clearly distinguishes between US and Imperial measurements.

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Number Base Converter

Convert numbers between binary, decimal, octal, and hexadecimal. Includes two's complement representation and ASCII character mapping for developer reference.

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Frequently Asked Questions

Are these developer tools really free?

Yes. Every developer tool on UtilDaily is completely free with no usage limits, no sign-up, and no paid tiers. The site is supported by non-intrusive advertising.

Is it safe to paste API keys or tokens into these tools?

Yes. All processing runs in your browser using JavaScript. Your data is never sent to any server. You can verify this by opening your browser's DevTools Network tab while using any tool — no outbound requests are made with your data.

Do these tools work offline?

Most developer tools work offline after your first visit. Tools like the JSON formatter, Base64 encoder, and UUID generator require no external resources and function entirely without a network connection.

What formats can I convert between?

UtilDaily supports several common data format conversions including JSON to CSV, CSV to JSON, and timestamp conversions. Each converter handles edge cases like nested objects, special characters, and various date formats.

Which browsers are supported?

All modern browsers are supported — Chrome, Firefox, Safari, and Edge. The tools use standard Web APIs including the Web Crypto API for hashing and encoding operations, available in every evergreen browser.

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