QuickTools
A growing collection of free, fast tools for developers, designers and everyday power users.
A growing collection of free, fast tools for developers, designers and everyday power users.
Showing 1–12 of 14 tools
Calculate percentage of a number, percentage change, what percent one number is of another, and percentage increase or decrease. Instant results with step-by-step formula explanations.
Calculate the final sale price, discount amount, and total savings from a percentage or fixed discount. Reverse-calculate the original price from a sale price. Instant results with a visual savings bar.
Calculate monthly loan payments, total interest, and total repayment for amortized or simple interest loans. Includes a full amortization schedule, yearly balance chart, and principal vs interest breakdown.
Calculate your monthly mortgage payment including principal, interest, property tax, homeowners insurance, PMI, and HOA fees. View a full amortization schedule, balance chart, extra payment savings, term comparison, and total loan cost.
Calculate return on investment (ROI), net profit, return multiple, and annualized ROI for any investment. Supports basic ROI and profit-based modes with a visual bar chart, profitability rating, and step-by-step breakdown.
Calculate compound interest growth with any compounding frequency — daily, monthly, quarterly, or annually. Add regular contributions, see a year-by-year growth schedule, effective annual rate (EAR), Rule of 72, and a visual balance chart.
Calculate your US federal income tax, Social Security, Medicare, and state income tax for 2025. See your net take-home pay by pay period, effective vs marginal tax rate, pre-tax deduction savings, and a full federal bracket breakdown.
Calculate tip amount, total bill, and per-person split instantly. Choose tip % by service quality, use quick presets (10–25%), split between any number of people, and apply rounding options. Includes a tipping guide by service type.
Calculate gross profit margin, net profit margin, operating margin, and markup percentage instantly. Supports simple (revenue vs cost) and detailed (COGS, OpEx, taxes) modes. Includes industry benchmarks, worked examples, and a margin vs markup guide.
Calculate how your investments grow over time with compound interest, regular monthly contributions, and optional inflation adjustment. See a year-by-year breakdown, total interest earned, real purchasing power, and Rule of 72 doubling time.
Calculate your cryptocurrency trading profit or loss instantly. Enter buy price, sell price, investment amount or coin quantity, exchange fees (Binance, Coinbase, Kraken presets), and an optional capital-gains tax rate to see net profit, ROI, and your exact break-even price.
Calculate the value of any gold item by weight, karat, and live spot price. Supports grams, troy ounces, kilograms, tola, tael, and grains — with 24K to 9K purity presets, dealer spread, jewellery making charges, and GST/VAT. Perfect for valuing coins, bars, and jewellery.