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    CalcPlanet — Free Online Calculators & Tools
    CalcPlanet

    Calculate Anything With Clear Formulas

    Free calculators and practical tools for money, health, math and everyday life. Instant results, clear formulas and no sign-up.

    💰 Mortgage📊 Percentage⚖️ BMI₿ Crypto Profit💵 Salary🧮 Tip
    ✓Free Calculators
    ✓Documented Formulas
    ✓Instant Results
    ✓No Sign-up

    START WITH A REAL ANSWER

    What do you need to work out?

    Pick a task and get straight to the calculator. No account or email required.

    01

    Calculate a percentage

    Discounts, increases, changes and percentage differences.

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    02

    Plan a mortgage

    Estimate payments, compare extra repayments and download the full schedule.

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    03

    Check your BMI

    Explore body mass index with the formula and limitations.

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    04

    Plan debt repayment

    Compare repayment scenarios and see the time and cost.

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    Calculations you can check

    See the formulas, testing approach and how to report an error.

    Practical calculation examples

    See how a result is calculated and which assumptions to check before relying on it.

    Check a discount

    15% × €80 = €12 → €80 − €12 = €68

    A 15% discount is calculated from the original price, not the discounted price. Check whether sales tax is included before comparing offers.

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    Understand a BMI estimate

    80 kg ÷ (1.80 m × 1.80 m) ≈ 24.7

    BMI uses weight divided by height squared. It is a screening measure, not a diagnosis or a direct measure of body fat.

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    Include trading fees

    €260 sale − €200 cost − €4 fees = €56

    The gain is €56 under these assumptions, before tax and any additional costs. A price increase alone does not equal your final return.

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    Compare mortgage offers

    Payment ≠ total housing cost

    An estimated principal-and-interest payment is only one part of a housing budget. Include property taxes, insurance and maintenance separately.

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    Free online tools

    141 free online tools for documents, images, QR codes, passwords and more. Open a tool to see how it handles your data.

    Browse all 141 free online tools

    Free Online Calculators

    Browse 12 categories — find the right tool instantly

    About CalcPlanet

    CalcPlanet is a free online platform with free calculators for math, finance, health, crypto, science, and more. Every tool is built with documented formulas and delivers instant results — no sign-up or paywall required.

    Whether you need to calculate your mortgage payment, check your BMI, or figure out compound interest — CalcPlanet provides professional, accurate tools that work on any device.

    Our mission is to make calculations accessible, fast, and reliable for everyone, everywhere.

    By · According to our Editorial Standards and Formula Sources, which explain how we document formulas and handle corrections.

    Frequently Asked Questions

    Are CalcPlanet calculators free to use?
    Yes. All calculators on CalcPlanet are completely free — no account, no email, no paywall. Ever.
    How accurate are the calculators?
    Every calculator uses documented, industry-standard formulas. Results are displayed with the underlying formula so you can cross-check the math.
    Do the calculators work on mobile?
    Yes. Every tool is fully responsive and shows a numeric keypad on mobile devices for fast, accurate input.
    How do I calculate a percentage?
    Divide the part by the whole, then multiply by 100. For example: (30 ÷ 150) × 100 = 20%.
    How do I calculate a monthly mortgage payment?
    Use the formula: P × [r(1+r)ⁿ] ÷ [(1+r)ⁿ − 1]. Or just use the Mortgage Calculator — it handles all the math instantly.
    How is BMI calculated?
    BMI = weight (kg) ÷ height² (m²). A BMI between 18.5–24.9 is considered healthy for most adults.
    Do I need to create an account to use CalcPlanet?
    No. Every calculator on CalcPlanet works instantly in your browser without an account, email, or sign-up. Your inputs stay on your device — we do not store or transmit calculation values.
    Can I embed CalcPlanet calculators on my own website?
    Yes. Most calculators have an 'Embed this calculator' button that generates a one-line iframe snippet. The embedded version is fully responsive and includes a 'Powered by CalcPlanet' link back.

    Explore CalcPlanet

    CalcPlanet is a free calculator platform covering finance, health, mathematics, crypto, science, statistics, engineering, construction, conversion, business and daily life. Open a calculator to see its inputs, method, worked example and limitations. You can explore the public calculators without creating an account.