Free online tools for developers and everyday use — JSON formatter, hash generator, BMI calculator, QR code generator, and more. No install needed.
25-min focus + 5-min break timer with session tracking
developerBuild cron expressions visually and preview next run times
developerEdit linear/radial gradients visually and copy CSS code
developerConvert text/URL to QR code with color and size options
developerConvert between binary, octal, decimal, and hexadecimal
developerConvert between Unix timestamps and date/time
converterConvert and compress PNG, JPG, and WebP images
developerGenerate random passwords with strength indicator
converterCheck the current time in major cities around the world
developerWrite markdown and preview rendered HTML in real time
developerCompare two texts and highlight differences line by line
formatterGenerate dummy text by paragraphs, sentences, or words
developerTest regex patterns with match highlighting and group capture
developerEncode and decode URL strings
calculatorCalculate D-day, date intervals, and add/subtract dates
calculatorCalculate loan repayments with amortization schedule
calculatorCalculate international age, Korean age, and zodiac sign
converterConvert length, weight, temperature, and volume units
formatterConvert between camelCase, snake_case, UPPER, and 9 more
developerGenerate UUID v4 in bulk with format options
developerGenerate SHA-256, SHA-384, SHA-512, and SHA-1 hashes
calculatorCalculate percentages, change rates, and ratios
converterConvert between HEX, RGB, and HSL color values
developerEncode and decode text to/from Base64
calculatorCalculate Body Mass Index (BMI) from height and weight
formatterCount characters, words, and bytes for any text
developerFormat, validate, and minify JSON
calculatorCalculate savings maturity amount from monthly deposits
calculatorCalculate compound interest with initial and monthly deposits
calculatorCompare monthly payments and fees by installment period
utilityCountdown timer and stopwatch with lap time recording
utilityEnter items and pick randomly with slot machine animation
utilityTake notes in your browser with auto-save and download
utilityConvert text to speech with voice, speed, and pitch control
converterResize images while keeping aspect ratio and converting formats
developerDecode JWT tokens, inspect claims, and encode with HS256
developerMinify, beautify, and compare HTML size