Free Online Calculators

Instant, accurate calculators for finance, health, math, and AI. No sign-up required.

10 calculators Instant results Mobile friendly Free to use

Financial Calculators

Plan your finances with confidence

Mortgage Calculator
Monthly payment breakdown, amortization table, LTV ratio, and PMI warning.
Financial
Loan Calculator
Monthly payments, total interest, and payoff date for personal, auto, or student loans.
Financial
Compound Interest
See investment growth over time with optional monthly contributions and visual chart.
Financial

Health Calculators

Know your numbers

BMI Calculator
Body Mass Index using WHO/CDC standards. Visual scale, healthy weight range.
Health
Calorie Calculator
BMR, TDEE, and daily calories for your goal using the Mifflin-St Jeor equation.
Health
Pregnancy Calculator
Due date, current week, trimester, and key milestones from LMP, conception, or due date.
Health

Math & Utility Calculators

Everyday calculations made easy

Percentage Calculator
Three modes: find X% of Y, what percent X is of Y, and percentage change.
Math
Tip Calculator
Tip amount, total bill, and per-person split with rounding options.
Math

AI Calculators

Tools for AI developers

Token Utilization
Estimate token count and context window usage across Claude, GPT, and Gemini models.
AI Tools
API Cost Calculator
Compare API costs across all major AI providers. Monthly cost estimates for any usage pattern.
AI Tools