Free online tools for developers and designers

Calculate monthly payments, total interest, and accelerated payoff scenarios.

Measure ROI, net profit, and annualized returns for investment decisions.

Estimate monthly and yearly take-home pay after taxes and deductions.

Convert currencies with browser-fetched exchange rates and common pairs.

Turn a rough goal into a structured prompt for ChatGPT, Claude, or Midjourney.

Evaluate regex patterns against test strings with immediate match highlighting.

Format, validate, minify, and inspect JSON with readable syntax output.

Compare two text or code blocks line by line and inspect differences quickly.

Format SQL queries with readable indentation and uppercase keywords.

Create cron expressions visually for hourly, daily, weekly, and monthly jobs.

Compress images in the browser with quality control and downloadable output.

Generate a palette of coordinated tints and shades from one base color.

Count words, characters, sentences, paragraphs, and estimated reading time.

Build linear or radial gradients with live preview and copy-ready CSS.

Generate downloadable QR codes for URLs, text, Wi-Fi strings, and contact info.

Compare dates and times across major time zones for remote collaboration.

Encode text to Base64 or decode Base64 back to plain text in one click.

Write Markdown on one side and preview formatted output instantly.

Generate secure passwords with custom length and character options.

Convert current, human-readable, and Unix timestamps in both directions.

Convert HEX, RGB, and HSL values with a live swatch and synchronized inputs.

Encode unsafe URL characters or decode encoded URLs instantly.

Inspect JWT headers and payloads locally in the browser.

Generate one or many UUID v4 identifiers instantly.

Remove duplicate lines from pasted text while keeping original order.

Convert text to uppercase, lowercase, title case, and sentence case.

Generate browser-side SHA hashes for text input.

Convert common length, weight, and temperature values quickly.

Escape or unescape HTML special characters safely.

Calculate days, weeks, and months between two dates.

Convert bytes, KB, MB, GB, and TB with binary or decimal units.

Sort multi-line text alphabetically, numerically, by length, or shuffle the list.

Generate filler paragraphs, sentences, or Chinese sample text for layouts, content blocks, and writing practice.

Browse common Unicode symbols and emoji, then copy any character with one click.

Convert uploaded images to PNG, JPG, or WebP locally in the browser.

Crop images to a centered area, resize to custom dimensions, and export the result.

Paste SVG code, preview it live, simplify markup, and export a cleaner version.

Use the native EyeDropper API when available to sample colors from the screen.

Run a countdown timer or stopwatch in the browser for deadlines, study sessions, and meetings.

Calculate exact age from a birth date and show the time until the next birthday.

Count weekdays between two dates and optionally exclude custom holidays.

Convert values between binary, octal, decimal, and hexadecimal formats.

Convert pasted CSV to JSON arrays and convert JSON arrays back into CSV.

Turn comma or line-separated values into JSON arrays, SQL IN lists, or quoted strings.

Calculate total bill, tip amount, and how much each person should pay.

Generate lightweight mock data for names, emails, phones, addresses, and UUIDs.

Tune offsets, blur, spread, opacity, and color to build copy-ready CSS shadows.

Generate standard or asymmetric border radius values with a live preview.

Configure flexbox or grid properties visually and copy the generated layout CSS.

Convert pixel values into rem and em units using a custom root font size.

Convert tabular data between TSV-style text and Markdown table syntax.

Solve common percent problems including X percent of Y and increase or decrease rates.

Convert Arabic numbers to Roman numerals and parse Roman numerals back to numbers.

Encode text into Morse code or binary and decode messages back into readable text.