All SpecWhale tools

Generate strong random passwords with browser cryptography.

Generate memorable passphrases from a bundled word list.

Estimate password strength locally without sending it anywhere.

Generate random integers in a chosen range.

Pick a random name or item from your list using a fair, uniform shuffle.

Split a list of names into random teams.

Roll dice for games, classrooms, and quick simulations.

Flip a fair virtual coin using cryptographically secure randomness.

Redact emails, phone numbers, URLs, and custom words locally.

Estimate uncompressed image size from width, height, and color depth.

Calculate CSS pixels, physical pixels, and device pixel ratio relationships.

Convert viewport widths into common responsive breakpoint ranges.

Generate fluid CSS clamp values from minimum and maximum sizes.

Calculate golden-ratio companion sizes for design and layout.

Calculate final document size after adding print bleed on every edge.

Estimate horizontal field of view from sensor width and focal length.

Estimate recording time from memory card size and camera bitrate.

Search common ISO and North American paper sizes.

Search common social media image dimensions for planning exports.

Search common screen, video, and monitor resolutions.

Convert teaspoons to tablespoons instantly (1 tsp = 0.333332 tbsp), free and accurate.

Convert tablespoons to cups instantly (1 tbsp = 0.0625002 cup), free and accurate.

Convert cups to US fluid ounces instantly (1 cup = 8 fl oz), free and accurate.

Convert bytes to megabytes instantly (1 B = 1.0000e-6 MB), free and accurate.

Convert gigabytes to terabytes instantly (1 GB = 0.001 TB), free and accurate.

Convert kilowatts to watts instantly (1 kW = 1.0000e+3 W), free and accurate.

Convert knots to miles per hour instantly (1 knot = 1.15078 mph), free and accurate.

Check WCAG contrast ratio between two hex colors.

Build Open Graph and Twitter card meta tags from page details.

Generate hreflang tags from locale and URL pairs.

Generate common redirect rules for Cloudflare Pages, Netlify, and Apache.

Decode JWT header and payload locally without verification.

Minify simple HTML by collapsing whitespace between tags.

Minify simple CSS by stripping comments and extra whitespace.

Format simple XML markup with indentation.

Calculate greatest common divisor and least common multiple from a list of integers.

Factor an integer into prime factors locally.

Calculate median, mode, minimum, maximum, and count from a list of numbers.

Generate SHA-256 checksums for local files in your browser.

Estimate whole and decimal months between two dates.

Calculate days, hours, and minutes until a future date.

Calculate deadline dates from a start date and duration.

Show current Unix time in seconds and milliseconds.

Estimate monthly payment, total paid, and total interest for an amortizing loan.

Calculate absolute and percentage investment return.

Calculate stock trade profit or loss from buy price, sell price, and shares.

Estimate retirement savings growth with monthly contributions.

Estimate freelance hourly rate from desired income, expenses, taxes, and billable hours.

Estimate body fat percentage using a simple circumference formula.

Estimate ideal weight range using a common height-based formula.

Estimate daily water intake from body weight.

Split calories into protein, carbs, and fat targets by percentage.

Estimate due date from last menstrual period date.

Estimate an ovulation window from cycle dates.

Calculate room area from length and width.

Estimate carpet area with waste allowance.

Estimate stair count from total rise and target riser height.

Estimate air conditioner BTU from room area.

Calculate aquarium volume from inside dimensions.

Estimate gravel volume from area and depth.