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121 Free Calculators

Boring Math Made Easy

Finance

UK £100k Tax Trap

Calculate how the 60% marginal rate affects you and find optimal pension contributions.

Most Used
Finance

UK Nursery Cost

Calculate childcare costs with free hours, Tax-Free Childcare, and government support.

Income

Go Full-Time Calculator

Calculate when you can quit your job to pursue freelancing or side hustle full-time.

Most Used
Income

Contractor vs Employee

Compare contractor rates vs salary accounting for taxes, benefits, and hidden costs.

Most Used
Finance

FIRE Calculator

Calculate your path to Financial Independence, Retire Early with Lean, Fat, and Coast FIRE projections.

Most Used
Finance

Mortgage Calculator

Calculate monthly payments, total interest, and loan costs for your home.

Most Used
Finance

Compound Interest

See how investments grow over time with the power of compound interest.

Most Used
Finance

Loan Calculator

Calculate monthly payments and total interest for any loan.

Health

BMI Calculator

Calculate your Body Mass Index and see healthy weight ranges.

Everyday

Percentage Calculator

Calculate percentages, percent change, and more with instant results.

Health

Calorie Calculator

Calculate your daily calorie needs (TDEE) based on activity level and goals.

Everyday

Tip Calculator

Calculate tips instantly and split bills between friends with ease.

Everyday

Unit Converter

Convert between length, weight, temperature, volume, and more.

Everyday

Age Calculator

Calculate your exact age in years, months, days with zodiac signs.

Income

Freelance Day Rate

Calculate your ideal freelance rate vs salary position, including tax adjustments and benefits analysis.

Income

Hourly to Salary

Convert hourly rate to annual salary with tax adjustments and take-home pay.

Income

Raise Calculator

See the lifetime value of salary increases and career compounding.

Income

Remote Work Savings

Calculate how much you save working from home - gas, time, food, and more.

Finance

Savings Goal

Calculate monthly contributions to reach your savings goal with inflation.

Finance

Emergency Fund

Calculate your ideal emergency fund size based on expenses and stability.

Finance

Debt Payoff Calculator

Compare snowball vs avalanche strategies to pay off debt faster.

Business

Side Hustle Profit

Determine if your side hustle is truly profitable with effective hourly rate.

Business

Etsy/eBay Fee Calculator

Compare marketplace fees and calculate your net profit on Etsy vs eBay.

Business

Break-Even Point

Calculate how many units you need to sell to cover business costs.

Home

Paint Calculator

Calculate paint needed for any room with gallons and shopping list.

Home

Flooring Calculator

Calculate flooring needed with pattern-specific waste factors and box counts.

Home

Mulch Calculator

Calculate how much mulch you need in cubic yards or bags for your garden beds.

Home

Electricity Cost

Calculate appliance running costs - daily, monthly, and yearly.

Events

Wedding Alcohol

Estimate beer, wine, and liquor for your celebration based on guest count.

Events

BBQ Calculator

Calculate meat, sides, and supplies for your cookout or BBQ party.

Events

Party Drink Calculator

Estimate non-alcoholic drinks, juice, water, and ice for your party or event.

Everyday

Discount Calculator

Calculate sale prices, percent off, and total savings on any purchase.

Everyday

Dog Age Calculator

Convert dog years to human years using accurate, science-based formulas.

Engineering

Reynolds Number

Calculate Reynolds number to determine flow regime (laminar, transitional, turbulent).

Engineering

Ideal Gas Law (PV=nRT)

Calculate pressure, volume, moles, or temperature using the ideal gas law.

Engineering

Pipe Flow Calculator

Size pipes, calculate velocity, or flow rate with velocity recommendations.

Engineering

LMTD Calculator

Calculate Log Mean Temperature Difference for heat exchanger design.

Engineering

Pressure Drop Calculator

Calculate pipe pressure drop using Darcy-Weisbach equation with friction factors.

Finance

401k Calculator

Project retirement savings with employer matching and compound growth.

Finance

HSA Calculator

Calculate triple tax advantage savings with contribution limits and long-term growth.

Health

Macro Calculator

Calculate your daily protein, carbs, and fat needs based on your goals.

Everyday

GPA Calculator

Calculate your semester and cumulative GPA with multiple grade scales.

Finance

UK Stamp Duty Calculator

Calculate SDLT, LBTT, or LTT with first-time buyer relief and additional property surcharge.

Finance

UK Child Benefit Calculator

Calculate Child Benefit and High Income Child Benefit Charge (HICBC) with pension strategies.

Finance

UK Student Loan Calculator

Project student loan repayments for Plan 1, 2, 4, 5 and Postgraduate with write-off dates.

Finance

UK Salary Sacrifice Calculator

Calculate tax and NI savings from pension, cycle-to-work, and EV salary sacrifice.

Finance

UK Pension Calculator

Project your retirement pot and income using the 4% rule with inflation adjustment.

Finance

UK Dividend Tax Calculator

Calculate tax on dividends and compare with salary for limited company directors.

Finance

US Tax Bracket Calculator

Find your 2025 federal tax bracket with visual breakdown of how your income is taxed.

Finance

Self-Employment Tax Calculator

Calculate 15.3% SE tax, federal income tax, and quarterly payments for freelancers.

Finance

Quarterly Estimated Tax Calculator

Calculate quarterly tax payments with safe harbor rules to avoid penalties.

Finance

Capital Gains Tax Calculator

Calculate tax on stocks, crypto, and investments with NIIT and long-term rates.

Finance

EU VAT Calculator

Calculate VAT for all 27 EU countries. Add, remove, or reverse calculate VAT.

Finance

EU Salary Calculator

Compare net salary across European countries after tax and social security.

Finance

Inflation Calculator

Calculate how inflation affects purchasing power using historical US CPI data from 1920-2025.

Finance

Net Worth Calculator

Calculate your total net worth by tracking assets and liabilities with category breakdowns.

Finance

US Paycheck Calculator

Calculate your take-home pay with federal taxes, state taxes, and deductions for all 50 states.

Machining

Speeds & Feeds Calculator

Calculate optimal RPM and feed rate for CNC milling with chip load and material data.

Aquarium

Fish Stocking Calculator

Calculate how many fish your aquarium can hold based on tank size, filtration, and plants.

Brewing

ABV Calculator

Calculate alcohol content from original and final gravity for beer, wine, mead, and cider.

Crafts

Clay Shrinkage Calculator

Calculate thrown vs fired pottery sizes for stoneware, porcelain, and earthenware clay bodies.

Crafts

Soap Lye Calculator

Calculate NaOH or KOH amounts for cold process soap with superfat and water ratios.

Machining

Tap Drill Calculator

Find the correct drill size for any thread with adjustable thread percentage.

Aquarium

Aquarium CO2 Calculator

Calculate CO2 levels from pH and KH readings with drop checker color guide.

Brewing

IBU Calculator

Calculate hop bitterness using Tinseth formula with multiple hop additions.

Crafts

Glaze Recipe Calculator

Scale pottery glaze recipes to any batch size with common material presets.

Crafts

Fragrance Calculator

Calculate fragrance oil amounts for candle making with wax-specific max loads.

Machining

Cutting Time Calculator

Estimate machining time for milling, turning, and drilling with cost calculation.

Aquarium

EI Dosing Calculator

Calculate Estimative Index fertilizer doses for planted aquariums.

Brewing

Mash Water Calculator

Calculate strike water temperature and sparge volumes for all-grain brewing.

Crafts

Kiln Cost Calculator

Calculate electricity cost for pottery kiln firings with cone temperature reference.

Crafts

Candle Wax Calculator

Calculate wax weight from container volume with wick sizing recommendations.

Machining

Tool Deflection Calculator

Calculate end mill deflection for CNC machining with stickout and cutting force analysis.

Aquarium

Water Change Calculator

Calculate how water changes affect aquarium parameters with dilution schedules.

Brewing

Priming Sugar Calculator

Calculate carbonation sugar for bottle conditioning with CO₂ volumes by style.

Brewing

Yeast Pitch Rate Calculator

Calculate proper yeast cell counts for healthy fermentation with starter sizing.

Crafts

Batch Cost Calculator

Calculate material costs, labor, overhead, and pricing for soap, candles, and crafts.

Finance

Scotland ADS Calculator

Calculate Additional Dwelling Supplement for second property purchases in Scotland.

Life

Baby Cost Calculator

Estimate the first-year costs of having a baby including essentials, healthcare, and childcare.

Events

Birthday Party Calculator

Plan and budget a birthday party with venue, food, decorations, and entertainment costs.

Finance

Buy vs Rent Calculator

Compare the long-term costs of buying vs renting a home over time.

Finance

Car Buy vs Lease

Compare the total cost of buying vs leasing a vehicle over time.

Events

Catering Calculator

Calculate food quantities and costs for catered events of any size.

Life

College ROI Calculator

Calculate the return on investment of a college degree based on costs and expected salary.

Events

Conference Room Calculator

Plan conference or meeting room layouts with seating capacity calculations.

Business

Consulting Rate Calculator

Calculate your ideal consulting hourly or daily rate based on expenses and target income.

Business

Employee Cost Calculator

Calculate the true cost of an employee including salary, benefits, taxes, and overhead.

Events

Event Seating Calculator

Calculate seating arrangements and capacity for weddings, conferences, and events.

Home

Fence Calculator

Calculate materials needed for fencing projects including posts, rails, and pickets.

Events

Graduation Party Calculator

Plan and budget a graduation party with food, decorations, and entertainment.

Events

Holiday Dinner Calculator

Calculate food quantities for Thanksgiving, Christmas, or holiday dinners.

Income

Job Offer Comparison

Compare multiple job offers including salary, benefits, commute, and growth potential.

Business

Marketplace Fees Calculator

Calculate seller fees across Amazon, eBay, Etsy, and other marketplaces.

Life

Moving Cost Calculator

Estimate the total cost of moving including movers, supplies, and travel expenses.

Income

Overtime Calculator

Calculate overtime pay including time-and-a-half and double-time rates.

Life

Pet Cost Calculator

Estimate the annual cost of pet ownership including food, vet, and supplies.

Business

Pricing Calculator

Calculate optimal product pricing with markup, margin, and profit analysis.

Business

Rental Property ROI

Calculate return on investment for rental properties including cash flow and cap rate.

Business

SaaS Metrics Calculator

Calculate key SaaS metrics including MRR, ARR, churn rate, and LTV.

Income

Salary to Hourly

Convert annual salary to hourly rate with tax and benefits adjustments.

Finance

UK SDLT Calculator

Calculate Stamp Duty Land Tax for property purchases in England and Northern Ireland.

Home

Solar Panel Calculator

Estimate solar panel system size, costs, and savings for your home.

Business

Startup Cost Calculator

Estimate initial costs for starting a business including legal, equipment, and marketing.

Finance

Subscription Audit

Track and analyze your subscriptions to find savings and reduce waste.

Home

Tile Calculator

Calculate tiles needed for floors or walls with waste factor and grout.

Life

Vacation Budget Calculator

Plan and budget your vacation including flights, hotels, food, and activities.

Income

W2 to 1099 Calculator

Convert W2 salary to equivalent 1099 contractor rate accounting for taxes and benefits.

Events

Wedding Budget Calculator

Plan your wedding budget with detailed cost breakdowns by category.

Health

Due Date Calculator

Calculate your pregnancy due date with LMP, conception, IVF, or ultrasound methods.

Health

Sleep Calculator

Find optimal bedtimes and wake times based on 90-minute sleep cycles.

Automotive

EV vs Gas Calculator

Compare total cost of ownership between electric and gas vehicles.

Health

TDEE Calculator

Calculate your Total Daily Energy Expenditure based on activity level and body composition.

Health

Body Fat Calculator

Estimate your body fat percentage using multiple measurement methods.

Health

Ovulation Calculator

Track your fertile window and predict ovulation dates based on your cycle.

Everyday

Currency Converter

Convert between world currencies with live exchange rates.

Everyday

Time Zone Converter

Convert times between world time zones with daylight saving support.

UK Tax

Council Tax Calculator

Calculate council tax bills by band and local authority across the UK.

UK Tax

Inheritance Tax Calculator

Calculate UK inheritance tax liability with nil-rate band and residence allowance.

UK Tax

UK Capital Gains Tax Calculator

Calculate CGT on property, shares, and other assets with annual exempt amount.

UK Tax

Stamp Duty Calculator Scotland (LBTT)

Calculate Land and Buildings Transaction Tax for property purchases in Scotland.

UK Tax

Stamp Duty Calculator Wales (LTT)

Calculate Land Transaction Tax for property purchases in Wales.

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