Online calculators

Every calculation you'll ever need

From quick tip splits to mortgage amortization and statistical analysis — DigitalCalculus brings 55+ accurate calculators into one clean, fast, browser-based workspace.

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55+
Calculators
4
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$0
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Compound Interest
Final value
after 10 years
$19,672
15
Free calculators
22
Pro — $5 one-time
18
Expert — $10 one-time
100%
Browser-based
All calculators
Find the right tool, fast
Free calculators open instantly — no account needed. Pro & Expert unlock with a one-time license key.
Financial20 calculators
%↗
Percentage Calculator
X% of Y, percentage change, reverse percent.
Free
🏷️↗
Sales Tax Calculator
Total price with any sales tax rate.
Free
🧾↗
Tip Calculator
Split bills with custom tip across any group.
Free
💱↗
Currency Converter
Convert between 30+ world currencies.
Free
🏦🔒
Loan Calculator
Monthly payment and full amortization table.
Pro
📊🔒
Interest Calculator
Simple vs compound interest comparison.
Pro
📈🔒
Compound Interest
Growth with contributions and compounding.
Pro
🔢🔒
Simple Interest
Principal × rate × time — fast and clear.
Pro
💰🔒
Savings Calculator
Goal planning with monthly contributions.
Pro
💳🔒
Credit Card Payoff
Time and cost to pay off any card balance.
Pro
🚗🔒
Auto Loan Calculator
Monthly car payment with trade-in.
Pro
🎓🔒
Student Loan
Repayment schedule for student debt.
Pro
📋🔒
Budget Calculator
Monthly income vs expenses breakdown.
Pro
💼🔒
Salary / Take-Home Pay
Annual to hourly, before and after-tax.
Pro
🏠🔒
Mortgage Calculator
Full amortization with overpayment modeling.
Expert
📅🔒
Amortization Calculator
Month-by-month principal and interest.
Expert
📉🔒
Investment Calculator
Portfolio growth with contributions.
Expert
🏖️🔒
Retirement Calculator
Savings needed for your retirement income.
Expert
📊🔒
Inflation Calculator
Real purchasing power over time.
Expert
💹🔒
ROI Calculator
Return on investment with annualized rate.
Expert
Health & Fitness12 calculators
⚖️↗
BMI Calculator
Body mass index with healthy range gauge.
Free
🎂↗
Age Calculator
Exact age in years, months, days.
Free
🎯↗
Ideal Weight Calculator
Healthy weight range by height and frame.
Free
🔥🔒
Calorie Calculator
Daily calorie needs by goal and activity.
Pro
💤🔒
BMR Calculator
Basal metabolic rate — Mifflin-St Jeor.
Pro
🥗🔒
Macro Calculator
Protein, carb, and fat targets for any goal.
Pro
📏🔒
Body Fat Calculator
Estimate body fat % from measurements.
Pro
⚡🔒
TDEE Calculator
Total daily energy expenditure.
Pro
❤️🔒
Target Heart Rate
5 training zones by age and resting HR.
Pro
🏃🔒
Pace Calculator
Running pace, speed, and finish time.
Pro
💪🔒
Lean Body Mass
Lean vs fat mass using multiple formulas.
Expert
🏋️🔒
Calories Burned
Calories burned by activity and weight.
Expert
Math14 calculators
🔬↗
Scientific Calculator
Full scientific with trig and logs.
Free
½↗
Fraction Calculator
Add, subtract, multiply, divide fractions.
Free
∑↗
Average Calculator
Mean, median, min, max from any list.
Free
🎲↗
Random Number Generator
Random integers or decimals in any range.
Free
σ🔒
Standard Deviation
Population and sample std dev.
Pro
x²🔒
Quadratic Formula
Solve ax²+bx+c=0 with real and complex roots.
Pro
⬛🔒
Area Calculator
Area of 8 shapes: circle, triangle, rect…
Pro
📦🔒
Volume Calculator
Cube, sphere, cylinder, cone and more.
Pro
△🔒
Triangle Calculator
Sides, angles, area — SSS, SAS, ASA, AAS.
Pro
📊🔒
Statistics Suite
Full descriptive stats with CI.
Expert
🎯🔒
Probability Calculator
Single and combined event probabilities.
Expert
⊞🔒
Matrix Calculator
Add, multiply, transpose, determinants.
Expert
📐🔒
Confidence Interval
90%, 95%, 99% confidence intervals.
Expert
Z🔒
Z-Score Calculator
Standardize values and find percentile.
Expert
Other / Utility9 calculators
📐↗
Unit Converter
Length, weight, temperature, volume, speed.
Free
📅↗
Date Calculator
Days between dates, add/subtract days.
Free
⏱️↗
Time Calculator
Add and subtract hours, minutes, seconds.
Free
🎓↗
GPA Calculator
Semester and cumulative GPA.
Free
⛽🔒
Fuel Cost Calculator
Trip fuel cost by mpg and gas price.
Pro
📝🔒
Grade Calculator
Weighted final grade from assignments.
Pro
🏗️🔒
Concrete Calculator
Cubic yards for slabs, columns, steps.
Expert
🏠🔒
Roofing Calculator
Roofing squares and materials needed.
Expert
⚡🔒
Electricity Cost
kWh usage and monthly bill estimation.
Expert
Pricing
Simple, one-time pricing

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Essential calculators for everyday tasks. No sign-up required.
  • 15 calculators
  • Tip & bill splitter
  • BMI & ideal weight
  • Unit & currency converter
  • Scientific calculator
  • Date & time tools
  • Pro calculators
  • Expert calculators
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Most popular
Pro
$5
one-time · key by email instantly
Financial and health tools for serious planners.
  • Everything in Free
  • Loan & interest calculators
  • Compound interest
  • Credit card payoff
  • Budget & salary tools
  • Calorie & macro calculator
  • Heart rate zones
  • Standard deviation
Expert
$10
one-time · all 55 calculators
Every calculator — finance, science, engineering, and statistics.
  • Everything in Pro
  • Mortgage modeler
  • Investment & ROI
  • Retirement calculator
  • Statistics suite
  • Probability & matrix
  • Confidence intervals
  • Concrete & roofing tools

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