All calculators
51 free tools, grouped by what you are trying to work out.
Finance
Loans, savings, investment and tax
Loan EMI Calculator Monthly instalment, total interest and a full amortization schedule for any loan. Compound Interest Calculator Grow a lump sum at any compounding frequency and see the year-by-year path. Simple Interest Calculator Interest charged only on the original principal — the straight-line case. SIP Calculator Project a monthly investment plan, including annual step-ups. SWP Calculator Withdraw monthly from a corpus and see how long it lasts. Retirement Calculator How large a corpus you need, and whether your saving rate gets you there. Inflation Calculator What an amount will be worth later — or what it was worth before. Discount Calculator Sale price, amount saved, and stacked or double discounts. Sales Tax & VAT Calculator Add tax to a price or strip it out of a tax-inclusive total. Tip & Bill Split Calculator Tip, total and the per-person share for any group size. Break-Even Calculator Units and revenue needed to cover fixed and variable costs. Profit Margin & Markup Calculator Margin, markup and profit from cost and price — the two are not the same. CAGR Calculator The single annual growth rate that connects a starting value to an ending one.
Health & Fitness
Body composition, energy and training
BMI Calculator Body mass index, its category, and the healthy weight range for your height. Calorie & TDEE Calculator Daily energy needs from BMR and activity, with targets for losing or gaining. Macro Calculator Split a calorie target into protein, carbs and fat in grams. Body Fat Calculator US Navy tape-measure body fat percentage, plus lean mass. Ideal Weight Calculator Four clinical formulas plus the healthy BMI range for your height. Water Intake Calculator Daily hydration target from bodyweight and exercise duration. Pregnancy Due Date Calculator Estimated due date, current week and trimester from your last period. Ovulation Calculator Fertile window and next period from your cycle length. Heart Rate Zone Calculator Maximum heart rate and the five training zones. One Rep Max Calculator Estimated 1RM from a set, plus a full percentage training table.
Math & Statistics
Algebra, geometry, stats and number theory
Percentage Calculator Every common percentage question in one place — of, change, and reverse. Statistics Calculator Mean, median, mode, range, variance and standard deviation for a data set. Geometry Calculator Area, perimeter, volume and surface area for common shapes and solids. Ratio Calculator Simplify ratios, scale them, and solve proportions for a missing term. Permutation & Combination Calculator nPr, nCr and factorials, with the ordering distinction made clear. Probability Calculator Single and combined event probability, plus odds conversion. GPA Calculator Credit-weighted grade point average on the standard 4.0 scale. Number Base Converter Convert between binary, octal, decimal and hexadecimal. Scientific Calculator A full expression calculator with functions, constants and precedence.
Date & Time
Ages, durations and working days
Age Calculator Exact age in years, months and days — plus zodiac, birthstone and next birthday. Date Difference Calculator The span between two dates in years, months, days, weeks and hours. Add or Subtract Days Calculator Find the date a given number of days, weeks, months or years away. Working Days Calculator Business days between two dates, excluding weekends and holidays. Time Duration Calculator Add up hours and minutes, or find the gap between two clock times.
Converters
Units, bases and data sizes
Everyday
Bills, fuel, energy and shopping
Home & Construction
Materials, paint, tiles and land
Tech & Media
Screens, files, bandwidth and colour
Aspect Ratio Calculator Simplify a resolution and resize while keeping proportions exact. Data Storage Converter Bits, bytes, kilobytes through petabytes — with the decimal/binary difference shown. Download Time Calculator How long a file takes at a given connection speed. Video & Audio File Size Calculator Estimate file size from bitrate and duration, or the bitrate to hit a size. IP Subnet Calculator Network address, broadcast, usable host range and mask from CIDR. Password Strength Calculator Entropy in bits and how long a brute-force attack would take.