Calculators
88 free online tools
About Calculators
From a quick tip split to a mortgage amortization schedule, calculators turn fiddly arithmetic into an instant answer — and ToolForge has one of the web's broadest collections, spanning financial, health and fitness, math, science, and everyday calculators. Whether you are projecting investment growth, finding your BMI, solving a quadratic, or estimating concrete for a slab, there is a dedicated calculator built for that exact job.
The financial calculators help with loans, interest, savings, and budgeting; the health and fitness set covers BMR, calories, body composition, and more; the math tools handle everything from fractions to standard deviation; the science calculators apply real physics and chemistry formulas; and the everyday calculators tackle dates, time, grades, fuel, and home projects. Every one runs instantly in your browser with no sign-up, and the more involved ones show their working — amortization tables, step-by-step breakdowns, and formulas — so you understand the result, not just see it.
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Related Categories
Loan Calculator
Calculate monthly payments, interest & total cost
EMI Calculator
Calculate Equated Monthly Installment
Compound Interest Calculator
Calculate growth with compound interest
Simple Interest Calculator
Calculate simple interest using I = PRT
Savings Calculator
Future value with regular deposits
Investment Calculator
ROI & growth projections
ROI Calculator
Calculate Return on Investment
Discount Calculator
Calculate % off sale price
Percent Off Calculator
Calculate percentage discounts
Sales Tax Calculator
Calculate sales tax on purchases
VAT Calculator
Add or remove VAT from prices
Tip Calculator
Calculate tips and split bills
Margin Calculator
Calculate profit margin and markup
Commission Calculator
Calculate sales commission earnings
Salary Calculator
Convert salary between hourly, weekly, monthly, annual
Budget Calculator
50/30/20 rule budget planning
Debt Payoff Calculator
Calculate debt payoff timeline
Credit Card Payoff Calculator
Calculate credit card payoff timeline
Student Loan Calculator
Calculate student loan repayment
Present Value Calculator
Calculate present value of future money
Future Value Calculator
Calculate future value of investments
Break-Even Calculator
Calculate business break-even point
BMI Calculator
Calculate body mass index (BMI)
BMR Calculator
Calculate Basal Metabolic Rate (BMR)
TDEE Calculator
Calculate daily energy expenditure
Calorie Calculator
Calculate goal-based daily intake
Ideal Weight Calculator
Calculate ideal weight range
Body Fat Calculator
Calculate body fat percentage
Lean Body Mass Calculator
Calculate lean body mass (LBM)
Protein Calculator
Calculate daily protein requirements
Macro Calculator
Calculate macronutrient splits
Target Heart Rate Calculator
Calculate training heart rate zones
One Rep Max Calculator
Calculate lift strength estimates
Pace Calculator
Calculate running pace or distance
Calories Burned Calculator
Calculate calorie burn from exercise
Water Intake Calculator
Calculate hydration needs
Sleep Calculator
Calculate optimal sleep schedules
Age Calculator
Calculate exact calendar age
Due Date Calculator
Estimate pregnancy due date
Ovulation Calculator
Calculate fertile windows
Period Calculator
Predict next menstruation dates
BAC Calculator
Calculate Blood Alcohol Concentration
Body Surface Area Calculator
Calculate Body Surface Area (BSA)
Fat Intake Calculator
Calculate calorie-based fat limits
Percentage Calculator
Calculate percentages, percentage increase/decrease
Fraction Calculator
Add, subtract, multiply, divide fractions
Average Calculator
Calculate mean, sum, count, min, max
Mean Median Mode Range Calculator
Calculate mean, median, mode, and range
Standard Deviation Calculator
Calculate population and sample standard deviation
Percentage Error Calculator
Calculate percentage, absolute, and relative error
Exponent Calculator
Calculate exponents and powers
Root Calculator
Calculate nth roots and square roots
Ratio Calculator
Simplify and scale ratios
Rounding Calculator
Round numbers to decimal places
GCF / LCM Calculator
Calculate Greatest Common Factor and Least Common Multiple
Factor Calculator
Find all factors and factor pairs of a number
Prime Factorization Calculator
Calculate prime factorization with factor tree
Probability Calculator
Calculate P(A), P(A∩B), P(A∪B), P(A|B)
Permutation & Combination Calculator
Calculate nPr permutations and nCr combinations
Area Calculator
Calculate area of rectangles, circles, triangles, and more
Volume Calculator
Calculate volume of 3D shapes
Pythagorean Theorem Calculator
Calculate missing side of right triangle using a²+b²=c²
Quadratic Formula Calculator
Solve quadratic equations with discriminant and roots
Scientific Notation Calculator
Convert to/from scientific notation and perform operations
Velocity Calculator
Calculate velocity using v = d/t
Force Calculator
Calculate force using F = ma
Kinetic Energy Calculator
Calculate kinetic energy using KE = ½mv²
Ohm's Law Calculator
Calculate voltage, current, resistance using V = IR
pH Calculator
Calculate pH from hydrogen ion concentration
Molarity Calculator
Calculate molarity using M = n/V
Ideal Gas Law Calculator
Calculate pressure, volume, moles, temperature using PV = nRT
Projectile Motion Calculator
Calculate projectile trajectory, range, time of flight
Resistor Color Code Calculator
Decode 4-band and 5-band resistor color codes
Density Calculator
Calculate density using ρ = m/V
Date Calculator
Calculate date differences and add/subtract days
Time Calculator
Add, subtract, and calculate time differences
Hours Calculator
Calculate work hours and overtime pay
GPA Calculator
Calculate GPA and cumulative GPA
Grade Calculator
Calculate final grade and course grades
Fuel Cost Calculator
Calculate fuel costs and MPG
Random Number Generator
Generate cryptographically secure random numbers
Dice Roller
Roll dice for games and simulations
Shoe Size Converter
Convert shoe sizes between regions
Time Zone Calculator
Convert time between time zones
Square Footage Calculator
Calculate area and material estimates
Concrete Calculator
Calculate concrete volume and bags needed
Tile Calculator
Calculate tiles needed for flooring
Wind Chill / Heat Index Calculator
Calculate wind chill and heat index
Frequently Asked Questions
Are these calculators accurate enough to rely on?
They use established formulas and show their working where it helps, so the math is sound. For consequential financial, medical, or engineering decisions, treat the results as a well-grounded estimate and confirm with a professional, since real outcomes depend on factors a calculator cannot capture.
Do the calculators save or share what I enter?
No. Every calculation runs locally in your browser, so the figures you enter — including financial and health data — are never uploaded or stored on a server.
What types of calculators are available?
The collection is organized into financial (loans, interest, investing, budgeting), health and fitness (BMI, calories, body metrics), math (algebra, statistics, geometry), science (physics and chemistry), and everyday calculators (dates, time, grades, home projects).
Do I need to install anything or create an account?
No. Every calculator works instantly in the browser with no installation, no sign-up, and no limit on how many calculations you run.
