Calculators
Easy-to-use interface
Accurate calculations every time
Works on mobile and desktop
Completely free, no limits
Available Calculators (13)
Popular
Graphing Calculator
Plot mathematical functions with symbolic expressions
Popular
Scientific Calculator
Advanced calculator with scientific functions
Popular
BMI Calculator
Calculate your Body Mass Index
Popular
Interest, Loan and Mortgage Calculator
Calculate interest rates, loan payments, mortgages, and total interest
Popular
Tip Calculator
Calculate tips and split bills
Percentage Calculator
Calculate percentages, increases, and decreases
Popular
Date Calculator
Add days to dates and calculate date differences
Calorie Calculator
Calculate daily calorie needs based on age, gender, and activity level
Protein Calculator
Calculate daily protein needs based on weight and activity level
Pregnancy Due Date Calculator
Calculate due date and weeks pregnant from last period
Paint Calculator
Calculate gallons of paint needed for room dimensions
Flooring Calculator
Calculate square footage and materials needed for flooring
Concrete Calculator
Calculate cubic yards of concrete needed for projects
Why Use Our Calculators?
Introduction
- Financial, health, and utility calculators with guardrails that prevent common input mistakes.
- Clear labels and helper text so non-experts can trust the numbers without reading a manual.
- Optimized for small screens to make quick decisions in stores, meetings, or travel.
- No sign-up; calculations run locally so you can rerun scenarios quickly.
When to Use
- Loan & Mortgage: payment sizing, comparing rates/terms, or pre-approval preparation.
- BMI/Calorie/Protein: health tracking, training plans, or doctor/coach conversations.
- Tip/Percentage/Date: on-the-go math for dining, discounts, and scheduling.
- Graphing/Scientific: coursework, quick plotting, or validating formulas.
- Paint/Flooring/Concrete: home projects needing materials and cost estimates.
How to Choose the Right Calculator
- Use Tip for single receipts; Percentage for discounts, markups, or tax scenarios.
- Pick Loan/Mortgage when amortization matters; switch to Interest-only if you just need simple growth math.
- Graphing for visual checks; Scientific for trig, logs, and multi-step equations.
- Project calculators (paint/flooring/concrete) include waste factors—use them instead of manual area math.
Tips for Better Results
- Enter units consistently (ft vs m) before area-based estimates to avoid costly overruns.
- Stress-test loans by adding 1-2% to rates to see payment sensitivity before committing.
- For nutrition, confirm activity multipliers match your routine; avoid overestimating burn.
- Save plots or outputs as screenshots for quick sharing with teammates or contractors.
Common Mistakes to Avoid
- Using monthly rates when the calculator expects annual APR leads to wrong payments; match the input labels.
- Mixing imperial and metric in project calculators skews material estimates; pick one system and stick to it.
- Relying on default activity multipliers for calories can overstate burn; adjust to your real training load.
- For tip/percentage math, ensure the base amount excludes taxes or add-ons if your locale uses pre-tax tipping.
- Graphing without labeling axes or units confuses results; add notes before sharing screenshots.