Date Calculator (Add / Subtract Days)
Add or subtract days, weeks, months or years from any date and instantly get the resulting date with its day of week. Perfect for deadlines, contract expiry and reminders.
Add or subtract days, weeks, months or years from any date and instantly get the resulting date with its day of week. Perfect for deadlines, contract expiry and reminders.
Three common percentage calculations in one place.
Bill total, tip %, and number of people โ get per-person amounts instantly.
Original price + discount % โ final price and savings.
Exact age in years, months and days โ plus days until your next birthday.
Body Mass Index with WHO categories: <18.5 underweight, 18.5โ24.9 normal, 25โ29.9 overweight, โฅ30 obese.
Initial deposit + monthly contributions, compounded monthly.
Monthly payment, total interest and payoff for a fixed-rate loan.
Length, weight and temperature conversions.
Days between two dates, or add/subtract days from a date.
Strong random passwords generated locally in your browser โ nothing is sent to any server.
Words, characters, sentences and reading time โ great for essays, posts and tweets.
Turn any URL or text into a QR code, generated locally in your browser.
Beautify or minify JSON.
Mifflin-St Jeor equation for BMR and daily calorie needs (TDEE), plus cutting/bulking targets.
Naegele's rule: estimated due date = first day of last menstrual period + 280 days.
Cryptographically random integers in any range โ great for giveaways and raffles.
Convert text to and from Base64 (UTF-8 safe).
Pick a color and get HEX, RGB and HSL values โ handy for design and front-end work.
Compress JPG/PNG/WebP entirely in your browser โ images never leave your device.
Combine multiple PDF files into one, in order โ processed entirely in your browser.
Extract a page range from a PDF into a new file.
Convert between GPS coordinates (WGS-84), the GCJ-02 datum used by Chinese map providers (AMap/Tencent, a.k.a. "Mars coordinates"), and Baidu's BD-09 datum.
Standard public algorithms; GCJ-02 โ WGS-84 uses iterative inverse with ~1 m accuracy. Coordinates outside mainland China are returned unchanged.
Convert decimal degrees (DD) to degrees-minutes-seconds (DMS) and back, e.g. 116.397428ยฐ = 116ยฐ23โฒ50.7โณ E.
Upload or paste a GeoJSON file and batch-convert every coordinate (Point / LineString / Polygon / FeatureCollection) between WGS-84 / GCJ-02 / BD-09 โ processed entirely in your browser.
Convert latitude/longitude (WGS-84) to and from UTM grid coordinates (Easting / Northing) using standard Transverse Mercator formulas (kโ = 0.9996). Zone is auto-detected from longitude, or set it manually.
Estimate your car loan payment with equal monthly installments: enter vehicle price, down payment, APR and term to get the monthly payment, total interest and true total cost of the car.
Add or subtract days, weeks, months or years from any date and instantly get the resulting date with its day of week. Perfect for deadlines, contract expiry and reminders.
Add or remove sales tax / VAT from any amount. Works for US state sales tax, UK VAT 20%, EU VAT 19-25%, GST and more โ just enter your rate.
Wake up refreshed: humans sleep in 90-minute cycles. Enter your wake-up time or bedtime and find the best times to sleep or wake, based on 4-6 full cycles plus about 14 minutes to fall asleep.
Flip one or many virtual coins with cryptographically secure randomness. Great for making decisions, games and probability homework.