Free Online Calculators
Find precise calculators for finance, math, science, and technical workflows. Start with the live tool clusters, then use the supporting explanations to understand the formula behind each result.
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Day 8 algebra and coordinate geometry calculators.
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Finance Calculators
LiveInterest, savings, loan, investment, budget, and payoff calculators for everyday money decisions.
Browse calculatorsMath Calculators
LivePercentage, fraction, ratio, algebra, geometry, trigonometry, and statistics calculators for school and everyday math.
Browse calculatorsScience Calculators
LiveChemistry, physics, and lab measurement calculators with formulas, unit conversions, and educational scope notes.
Browse calculatorsEngineering Calculators
LiveFluid, mechanics, and beam calculators with formulas, unit conversions, and explicit simplified assumptions.
Browse calculatorsBuilt for decisions that need numbers, units, and context
Auditable inputs
Inputs stay labeled by unit, rate, term, and formula variable so users can check assumptions before trusting a result.
Comparison-ready summaries
Results show totals, intermediate values, and scenario-sensitive notes for comparing payments, growth, ratios, and geometry measurements.
Formula and source context
Formula notes point users toward the calculation method, while guide pages link to authoritative references for finance, math, and units.
Sources behind the formulas and data notes
| Topic | Used for | Reference |
|---|---|---|
| Compound growth and savings | Interest, future value, savings goal, APY, and CD examples | Investor.gov financial calculators |
| Consumer inflation | Inflation and purchasing-power examples based on CPI context | U.S. Bureau of Labor Statistics CPI calculator |
| Debt-to-income ratio | Debt, mortgage, and budget pressure explanations | Consumer Financial Protection Bureau |
| Geometry and trigonometry formulas | Area, circle, Pythagorean theorem, angles, and unit circle notes | OpenStax math references |
| Radians and angle units | Degrees-to-radians conversion and trigonometry references | NIST SI unit guidance |
Finance and math calculators available now
Savings and investing
Compound Interest Calculator
Project future value, total deposits, and interest earned with recurring monthly contributions and compounding controls.
Use calculatorInterest formulas
Simple Interest Calculator
Calculate interest and final value using the simple interest formula for loans, savings notes, and classroom examples.
Use calculatorLoans
Loan Payment Calculator
Estimate monthly payments, total interest, and payoff cost for fixed-rate personal loans and installment plans.
Use calculatorLoans
Mortgage Payment Calculator
Plan home loan payments with principal, interest, property tax, insurance, HOA, and down-payment assumptions.
Use calculatorLoans
Auto Loan Calculator
Calculate vehicle payments after price, down payment, trade-in value, tax, fees, APR, and repayment term.
Use calculatorLoans
Amortization Schedule Calculator
Create a repayment schedule with yearly principal, interest, balance, and optional extra-payment savings.
Use calculatorSavings
APY Calculator
Convert nominal annual rates and compounding schedules into annual percentage yield for savings comparisons.
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Savings Goal Calculator
Find the monthly amount needed to reach a target balance by a chosen date or savings horizon.
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CD Interest Calculator
Estimate certificate of deposit maturity value, interest earned, effective APY, and early withdrawal impact.
Use calculatorSavings
Emergency Fund Calculator
Calculate an emergency fund target, savings gap, coverage months, and time to goal from monthly expenses.
Use calculatorInvesting
ROI Calculator
Calculate return on investment from initial cost, ending value, cash flows, fees, and holding period.
Use calculatorInvesting
CAGR Calculator
Calculate compound annual growth rate, total growth, and absolute change between beginning and ending values.
Use calculatorInvesting
Future Value Calculator
Project present value, monthly contributions, rate, and compounding assumptions into a future balance.
Use calculatorInvesting
Present Value Calculator
Discount a future amount back to today with rate, timeline, compounding frequency, and discount factor.
Use calculatorBudget & Debt
Budget Percentage Calculator
Convert budget categories into percentages of monthly income and flag remaining or over-budget cash flow.
Use calculatorBudget & Debt
Debt Payoff Calculator
Estimate debt-free time and interest cost with snowball or avalanche payoff ordering.
Use calculatorBudget & Debt
Debt-to-Income Ratio Calculator
Calculate front-end and back-end DTI from gross income, housing payment, and monthly debt obligations.
Use calculatorBudget & Debt
Credit Card Payoff Calculator
Estimate credit card payoff time, interest cost, and three-year payment target from APR and payments.
Use calculatorIncome & Inflation
Inflation Calculator
Calculate future cost, cumulative inflation, buying power, and annual projection from rate and time.
Use calculatorIncome & Inflation
Salary to Hourly Calculator
Convert annual salary into hourly pay, pay-period amounts, scheduled hours, and PTO-adjusted rate.
Use calculatorIncome & Inflation
Hourly to Salary Calculator
Convert hourly wage, regular hours, overtime, paid weeks, and unpaid time off into annual pay.
Use calculatorCore Math
Percentage Calculator
Calculate percent of a value, part as percent of total, percent change, and increase or decrease scenarios.
Use calculatorCore Math
Fraction Calculator
Simplify fractions and calculate addition, subtraction, multiplication, division, decimals, and percent forms.
Use calculatorCore Math
Ratio Calculator
Simplify ratios, calculate shares of a total, and scale an equivalent ratio from a target quantity.
Use calculatorAlgebra & Coordinate Geometry
Linear Equation Solver
Solve ax + b = c equations, isolate x, and identify one-solution, identity, or no-solution cases.
Use calculatorAlgebra & Coordinate Geometry
Slope Calculator
Calculate slope from two points with rise, run, y-intercept, point-slope form, and vertical-line handling.
Use calculatorAlgebra & Coordinate Geometry
Midpoint Calculator
Find the midpoint between two coordinate points with x and y averages and ordered-pair output.
Use calculatorAlgebra & Coordinate Geometry
Distance Formula Calculator
Calculate straight-line distance between two coordinate points with delta x, delta y, and squared distance.
Use calculatorGeometry
Area Calculator
Calculate rectangle, triangle, circle, and trapezoid area with formula-backed square-unit results.
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Perimeter Calculator
Calculate square, rectangle, triangle, and circle perimeter or circumference with unit-aware formulas.
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Circle Calculator
Calculate diameter, circumference, area, sector area, and arc length from radius and angle inputs.
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Triangle Calculator
Calculate triangle perimeter, semiperimeter, Heron area, base-height area, side validity, and side type.
Use calculatorTrigonometry
Pythagorean Theorem Calculator
Calculate hypotenuse, missing leg, squared terms, and right-triangle checks from side inputs.
Use calculatorTrigonometry
Right Triangle Calculator
Calculate hypotenuse, area, perimeter, acute angles, sine, cosine, and tangent from two legs.
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Unit Circle Values Reference
Review common degree, radian, sine, cosine, tangent, and coordinate values for unit circle study.
Use calculatorStatistics
Mean Median Mode Calculator
Calculate mean, median, mode, range, sum, minimum, maximum, and sorted values from a pasted dataset.
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Standard Deviation Calculator
Calculate sample and population standard deviation, variance, mean, and squared-deviation checks.
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Percentile Calculator
Calculate percentile values with nearest-rank and interpolated methods, sorted values, and rank checks.
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Z Score Calculator
Calculate z-score, distance from mean, and approximate normal percentile from value, mean, and standard deviation.
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Math Formula Library
Review formulas for arithmetic, algebra, geometry, trigonometry, statistics, notation, and number theory.
Use calculatorNotation & Number Theory
Scientific Notation Calculator
Convert values into scientific notation, engineering notation, e notation, coefficient, and exponent form.
Use calculatorNotation & Number Theory
Prime Factorization Calculator
Find prime factors, exponent form, expanded factors, prime status, and positive divisor count.
Use calculatorNotation & Number Theory
GCD and LCM Calculator
Calculate greatest common divisor, least common multiple, and prime factor audit rows for integer lists.
Use calculatorChemistry
Molar Mass Calculator
Calculate molar mass from a chemical formula with element counts, atomic weights, and percent-by-mass rows.
Use calculatorChemistry
Dilution Calculator
Calculate stock volume, solvent volume, dilution factor, and final moles from M1V1 = M2V2.
Use calculatorChemistry
pH Calculator
Convert pH, pOH, hydrogen ion concentration, and hydroxide ion concentration with classroom chemistry formulas.
Use calculatorPhysics
Ohm's Law Calculator
Calculate voltage, current, resistance, and power with ampere, milliampere, ohm, kilohm, volt, and watt conversions.
Use calculatorPhysics
Electrical Power Calculator
Calculate watts, kilowatts, joules, kWh, and equivalent resistance from voltage, current, and run time.
Use calculatorPhysics
Kinetic Energy Calculator
Calculate kinetic energy, momentum, and energy conversions from mass and speed inputs.
Use calculatorPhysics
Velocity and Acceleration Calculator
Calculate final velocity, displacement, acceleration, average velocity, and motion unit conversions.
Use calculatorLab measurements
Significant Figures Calculator
Count significant figures, decimal places, rounded values, scientific notation, and ambiguous trailing-zero cases.
Use calculatorLab measurements
Percent Error Calculator
Calculate signed error, absolute error, relative error, and percent error from measured and accepted values.
Use calculatorLab measurements
Density Calculator
Calculate density from mass and volume with kg/m^3, g/cm^3, g/mL, kg/L, lb/ft^3, and lb/gal outputs.
Use calculatorFluids
Reynolds Number Calculator
Calculate Reynolds number from density, velocity, characteristic length, and viscosity with simplified pipe-flow regime notes.
Use calculatorMechanics
Stress and Strain Calculator
Calculate axial stress, strain, microstrain, percent strain, and implied Young's modulus from force and elongation.
Use calculatorStructures
Beam Load Calculator
Estimate simple beam deflection, maximum moment, and shear for center point load or uniform load cases.
Use calculatorPractical calculators with context
Toolarithm's calculator hub is built around the same principle as the graph paper tools: the useful part should be visible immediately, and the supporting explanation should help users trust the result. A calculator page should not force someone to read through a long article before they can enter a number. It should open with the inputs, show the answer clearly, explain the formula, and provide enough context to use the result responsibly. That is especially important for finance calculators, where small changes in interest rate, term, or contribution timing can create very different outcomes.
The live calculator set now covers percentage, fraction, ratio, linear equations, slope, midpoint, distance formula, geometry, trigonometry, statistics, scientific notation, prime factorization, GCD, LCM, savings goals, APY conversion, CD interest, emergency fund planning, ROI, CAGR, future value, present value, budget percentages, debt payoff, debt-to-income ratio, credit card payoff, inflation, salary-to-hourly conversion, hourly-to-salary conversion, interest growth, fixed loan payments, mortgage estimates, auto loans, and amortization schedules. That combination supports common user intent across core math, income planning, saving, investing, borrowing, budgeting, teaching, and planning. The math tools explain percentages, fractions, ratios, formulas, geometric units, trigonometric angle measures, dataset statistics, powers of ten, and integer factorization. The savings tools show target amounts, compounding, yield, and coverage; the investment tools explain return and time value; the income tools convert pay and inflation assumptions; the budget tools connect debt decisions to monthly cash flow; and the loan calculators show monthly payment, payoff cost, and repayment structure. Future calculator releases will expand into probability, physics, chemistry, and engineering tools. Each new page should add a calculation users can inspect: named variables, formulas, edge cases, unit behavior, practical examples, and links to the closest related tool or guide.