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Finance, health, math, and everyday calculators β€” all peer-reviewed, all free, no sign-up required.

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Every calculator is free, instant, and works on any device.

Most popular

Popular
Mortgage Calculator

Calculate monthly repayments, total interest, and transfer taxes for AU, US, UK, NZ, CA, and SG.

Popular
Compound Interest Calculator

See how your money grows with compound interest. Scenario comparison, PDF export, and interactive growth charts.

Popular
Loan Repayment Calculator

Calculate monthly repayments, total interest, and how extra payments slash your loan term.

Popular
BMI Calculator

Check your BMI instantly. Get personalised health category insights, ideal weight range, and body fat estimate.

Popular
Calorie Calculator

Find your daily calorie needs (TDEE) and macro targets for weight loss, maintenance, or muscle gain.

Popular
Percentage Calculator

Four percentage calculators in one: X% of Y, percentage change, X is what % of Y, and percentage difference.

πŸ‡¦πŸ‡Ί Australia
GST Calculator Australia

Add or remove 10% Australian GST instantly. Also supports NZ, Singapore, India, UK VAT, and custom rates.

Popular
Age Calculator

Find your exact age in years, months, days, and hours. See birthday countdown, zodiac sign, and fun stats.

Why Calculy?

Built to be the calculator site you actually want to use.

Instant results

Results update in real time as you type or drag. No loading screens, no delays, no page refreshes.

Visual by default

Every calculator includes charts, breakdowns, and visual aids β€” not just a raw number.

Mobile first

Designed for touch from the start. Sliders, big tap targets, and layouts that work on any screen size.

Private

All calculations run in your browser. No data sent to our servers without your consent.

Accurate formulas

Every formula is sourced from official financial, health, and scientific standards. Peer-reviewed.

Save & share

Save your calculations, share links with pre-filled values, and export to PDF. Free.

All calculators

Every tool we offer β€” free, instant, no sign-up.

πŸ’° Finance

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Popular
Mortgage Calculator

Calculate monthly repayments, total interest, and transfer taxes for AU, US, UK, NZ, CA, and SG.

πŸ‡¦πŸ‡Ί Australia
Mortgage Calculator Australia

AU-specific mortgage calculator with state-by-state stamp duty, LMI estimates, and amortisation schedule.

Popular
Compound Interest Calculator

See how your money grows with compound interest. Scenario comparison, PDF export, and interactive growth charts.

Popular
Loan Repayment Calculator

Calculate monthly repayments, total interest, and how extra payments slash your loan term.

Savings Calculator

See how your savings grow with compound interest and regular contributions. Year-by-year breakdown with charts.

Trending
SIP Calculator

Calculate how monthly investments grow into serious wealth over time through the power of compounding.

Popular
Retirement Calculator

Will your super last through retirement? Calculate your corpus, monthly drawdown, and shortfall.

Trending
Inflation Calculator

See how inflation erodes purchasing power. Use historical AU CPI rates or enter a custom rate.

πŸ‡¦πŸ‡Ί Australia
Superannuation Calculator

Project your super balance at retirement. Compare against ASFA comfortable retirement standard. Updated for 11.5% SGC (2024–25) with voluntary contribution modelling.

πŸ‡¦πŸ‡Ί Australia
Rent Affordability Calculator

How much rent can you afford? Uses the 30% income rule with Australian city median rent comparisons and a full budget breakdown.

πŸ‡¦πŸ‡Ί Australia
Income Tax Calculator

Calculate Australian income tax, Medicare levy, and take-home pay for 2024–25. Updated for Stage 3 tax cuts. Full bracket breakdown and pay period comparison.

πŸ‡¦πŸ‡Ί Australia
HECS / HELP Calculator

Calculate your HECS/HELP repayment for 2024–25, years to pay off (with indexation), and how student debt reduces your mortgage borrowing power.

πŸ‡¦πŸ‡Ί Australia
Stamp Duty Calculator

Calculate transfer duty for all Australian states and territories β€” NSW, VIC, QLD, WA, SA, TAS, ACT, NT β€” with first home buyer concessions.

πŸ‡¦πŸ‡Ί Australia
Borrowing Power Calculator

How much can you borrow for a home loan? Uses bank-style serviceability estimate with APRA's 3% buffer and HEM-inspired expense floor.

πŸ‡¦πŸ‡Ί Australia
LMI Calculator

Estimate Lenders Mortgage Insurance for Australian home loans. See the cost at different LVRs and how much you need to save to avoid LMI.

❀️ Health

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Popular
BMI Calculator

Check your BMI instantly. Get personalised health category insights, ideal weight range, and body fat estimate.

Popular
Calorie Calculator

Find your daily calorie needs (TDEE) and macro targets for weight loss, maintenance, or muscle gain.

Body Fat Calculator

Calculate body fat percentage using the US Navy method or BMI formula. See lean mass and health category.

Popular
Pregnancy Due Date Calculator

Calculate your due date using LMP, conception date, IVF transfer, or ultrasound. See trimester and milestones.

πŸ“ Math

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Popular
Percentage Calculator

Four percentage calculators in one: X% of Y, percentage change, X is what % of Y, and percentage difference.

πŸ‡¦πŸ‡Ί Australia
GST Calculator Australia

Add or remove 10% Australian GST instantly. Also supports NZ, Singapore, India, UK VAT, and custom rates.

Popular
Age Calculator

Find your exact age in years, months, days, and hours. See birthday countdown, zodiac sign, and fun stats.

Trending
Discount Calculator

Find the sale price after any percentage discount. Quick-reference grid for common discounts from 5–80%.

Learn the maths behind the calculators

Free guides explaining the formulas, concepts, and real-world applications.

View all guides β†’

Why Calculy exists

Most calculator websites were built in the early 2000s and haven't changed since. They give you a number β€” no context, no explanation, no chart showing what that number actually means over time.

Calculy was built to answer the question that comes after the number: what does this mean, and what should I do about it? Every calculator includes worked examples, visual breakdowns, and contextual explanations written in plain language β€” not financial jargon.

The Australian-specific tools β€” mortgage calculator, stamp duty, borrowing power, and HomeVerdict β€” use the same assessment criteria Australian banks apply, not simplified approximations. The formulas are documented, the sources are cited, and the methodology is transparent.

Calculy is free, requires no sign-up, and runs entirely in your browser. Your financial information stays on your device.

How our calculators work

πŸ“
Peer-reviewed formulas
Every calculation uses formulas sourced from official standards β€” APRA guidelines for Australian mortgage tools, WHO standards for health calculators, and ATO tax tables for income estimates. We cite our sources.
⚑
Real-time calculation
Results update instantly as you type or drag sliders β€” no submit button, no page refresh. The chart redraws in milliseconds because all computation runs in your browser, not on a server.
πŸ‡¦πŸ‡Ί
Australia-specific where it matters
Australian mortgage, stamp duty, borrowing power, and superannuation calculations use current 2024–25 data: ATO tax brackets, APRA's 3% interest buffer, and state-by-state transfer duty rates for all 8 states and territories.
πŸ€–
AI-enhanced for property decisions
HomeVerdict combines bank-style financial calculations with AI-generated plain-English explanations β€” giving you a Comfortable, Stretch, High Risk, or Proceed with Caution verdict on any Australian property purchase.

Methodology and sources

Calculy's calculators are built on publicly available, authoritative data sources. We do not invent formulas or use proprietary estimates.

APRA
Australian Prudential Regulation Authority
Interest rate buffers, lending standards, DTI guidelines for mortgage and HomeVerdict calculators
ATO
Australian Taxation Office
2024–25 income tax brackets, Medicare levy, and HECS repayment thresholds for income and borrowing power tools
ABS
Australian Bureau of Statistics
Household Expenditure Survey data underpins the HEM-inspired expense floor used in HomeVerdict and borrowing power calculations
WHO
World Health Organization
BMI classification thresholds and body mass index methodology for all health calculator tools

All calculators provide educational estimates only and do not constitute financial, health, or legal advice. Results should be verified with qualified professionals before making financial decisions.Full disclaimer β†’