Tech & Web Calculators
Subnets, download times, screen sizes and other numbers engineers look up.
Aspect Ratio CalculatorSimplify any width and height to its lowest-terms aspect ratio, or enter a ratio and a new width to solve for the matching height. Common ratios included.Bandwidth CalculatorWork out required network bandwidth for concurrent users or video streams, and estimate monthly data usage from your daily viewing hours.Binary CalculatorBinary calculator that converts between decimal, binary, octal and hexadecimal at once. Decimal 42 equals binary 101010, octal 52 and hex 2A.Color Contrast Checker (WCAG)Check the WCAG 2.1 contrast ratio between a foreground and background hex color, with instant AA and AAA pass/fail results for text and UI components.Download Time CalculatorWork out download time from file size and connection speed. Handles the Mbps-vs-MB/s bits-to-bytes conversion automatically, with a realistic-speed estimate.Hex to RGB ConverterConvert a hex color code to its RGB and HSL values, or enter RGB numbers to get the matching hex code. Supports both #RRGGBB and shorthand #RGB formats.Megapixel CalculatorConvert pixel dimensions to megapixels and aspect ratio, or solve megapixels + ratio back to width and height. Includes max print size at any DPI.Password Entropy CalculatorEstimate a password's entropy in bits from its length and character set, with illustrative brute-force crack times. For randomly generated passwords only.PPI CalculatorCalculate pixels per inch (PPI), dot pitch and total megapixels from a screen's resolution and diagonal size. Works for monitors, TVs and phone displays.Print Size CalculatorWork out how large an image can print at a given DPI, or the DPI needed for a target print size, with a plain-language photo quality verdict.Subnet CalculatorEnter an IPv4 address and CIDR prefix to get the network address, broadcast address, usable host range, subnet mask and wildcard mask instantly.TV Size CalculatorFind the recommended TV size for your viewing distance, or the recommended distance for a TV size, using THX (~40°) and SMPTE (~30°) angle conventions.Typing Speed Calculator (WPM)Calculate gross and net words per minute from characters (or words) typed, time taken and errors, plus your accuracy percentage against speed benchmarks.