All 155 calculators

Compare the payment, the total interest, and what happens if you take the 30 and invest the difference.

Calculate capitalisation rate and net operating income, and check the value the market implies for the property.

Estimate lender fees, title charges, prepaids, and transfer taxes to find the real cash you need at closing.

Project the long-run cost of HOA dues, including increases and special assessments, and see how much buying power they consume.

Work backwards from your income, debts, and down payment to the maximum home price a lender will approve.

Run the 70% rule, project net profit and ROI, and find your maximum allowable offer on a flip.

Estimate your full monthly payment including taxes, insurance, PMI, and HOA — plus total interest and an amortization schedule.

See how much sooner you finish and how much interest you save by paying extra each month or in lump sums.

Estimate your monthly private mortgage insurance and work out exactly when you can have it removed.

Convert an assessed value and tax rate or mill levy into your annual and monthly property tax bill.

See your new payment, monthly savings, break-even point, and lifetime cost before you refinance.

Compare the true net cost of renting against buying over your actual time horizon, including equity, appreciation, and opportunity cost.

Underwrite a rental property: monthly cash flow, cap rate, cash-on-cash return, and the 1% rule.

Work out what you actually walk away with after commission, closing costs, repairs and paying off the mortgage.

Project your 401(k) balance at retirement including employer match, contribution increases, and fees.

Project dividend income, reinvestment growth, and yield on cost over time.

Calculate the discount, guaranteed return, and tax treatment of an employee stock purchase plan with a lookback.

Find your financial independence number and the year you can retire early, based on savings rate and spending.

Estimate a defined-benefit pension from your years of service and final average salary, and compare it against a lump sum offer.

See how long your portfolio lasts, how much you can withdraw each year, and where Social Security fits in.

Estimate the tax cost of converting traditional IRA money to a Roth and compare long-run after-tax outcomes.

Estimate withholding at vest, the gap versus your actual tax rate, and capital gains if you hold the shares.

See how claiming early or delaying changes your monthly benefit and your lifetime total.

Project a 529 balance against rising tuition costs and find the monthly contribution that closes the gap.

Find the compound annual growth rate between two values, and see why it differs from the average yearly return.

Project maturity value for a certificate of deposit, compare terms, and check the cost of breaking it early.

See what regular contributions plus compound growth turn into over time — and how much of the total is growth rather than deposits.

Project a dividend portfolio with reinvestment, dividend growth and share price appreciation over time.

Compare investing a lump sum now against spreading it out over time, in both a rising and a falling market.

Size a realistic emergency fund from your actual essential expenses, then see how long it takes to fill the gap.

See what your money will actually be worth later, and what you would need to keep the same standard of living.

Turn a starting and ending value into total return, annualised return (CAGR), and a comparison against a benchmark.

Discount a stream of cash flows to present value, find the internal rate of return, and see the payback period.

Estimate how long money takes to double at a given return — and check the shortcut against the exact maths.

Work out the monthly deposit that actually reaches your target — or how long your current pace will really take.

Calculate what a high-yield savings account or CD actually pays, including the difference between APR and APY.

See how long a card balance really takes to clear, what the minimum payment costs you, and what a balance transfer saves.

Compare keeping your current debts against rolling them into one loan — including the fee and the longer term.

Compare the avalanche and snowball methods across all your debts, and see exactly what an extra payment buys you.

Work out the front-end and back-end DTI that lenders use, and see how much room you have left to borrow.

Generate a full payment schedule for any loan and see exactly how each payment splits between interest and principal.

Calculate the payment on a personal loan and the true APR once origination fees are included.

Work out your monthly payment, total interest, and what refinancing or an extra payment would actually save.

Calculate short- and long-term capital gains tax, including the 3.8% net investment income tax and state tax.

Estimate your 2025 federal income tax, effective rate, marginal bracket, and refund or balance due.

Turn your salary into an actual net paycheck after federal tax, FICA, state tax, and pre-tax deductions.

Calculate SE tax, the deductible half, the QBI deduction, and quarterly estimated payments for 1099 income.

Work out the tax on a specific stock sale from share count, purchase price, sale price, and holding period.

Calculate body mass index, see your category, and find the weight range that would put you in the healthy band.

Estimate body fat percentage with the US Navy circumference method, plus lean mass and category.

Find your BMR, maintenance calories, and daily targets for losing, maintaining, or gaining weight.

Calculate your five training zones from maximum and resting heart rate using the Karvonen method.

Compare the four classic ideal body weight formulas against the healthy BMI range for your height.

Estimate lean mass and fat mass from height and weight alone, using the Boer, James and Hume formulas.

Split your calorie target into protein, carbohydrate, and fat grams for your goal and training style.

Estimate your 1RM from a set you have actually done, compare the major formulas, and get your training percentages.

Find your likely fertile window and next few cycles from your last period and typical cycle length.

Work out an estimated due date from your last period, conception date, or IVF transfer, with a full milestone timeline.

Find your daily protein target based on body weight, goal, and training volume — with per-meal distribution.

Convert between pace, speed, and finish time, and get equivalent race predictions and training paces.

Find bedtimes and wake times that land between sleep cycles, so you wake in light sleep instead of deep sleep.

Estimate daily fluid needs based on body weight, activity, climate, and exercise duration.

Work out the car price your income supports, including insurance, fuel and maintenance — not just the loan payment.

Calculate your monthly car payment, total interest, and how trade-in, tax, and fees change the loan.

Find what your vehicle truly costs to run per mile, including depreciation, insurance and maintenance.

Calculate the cost to charge an electric vehicle at home or on the road, and compare it against gasoline.

Calculate the fuel cost of a trip or a year of driving, and compare two vehicles side by side.

Compare the total cost of leasing against buying a car over the same period, including resale value.

Calculate real-world fuel economy from your fill-ups and convert between MPG, L/100km and km/L.

Budget a road trip including fuel, lodging, food, tolls, and per-person cost splitting.

Compare two tire sizes for diameter, speedometer error and clearance before you commit to a change.

Check your real towing headroom against GVWR, GCWR, payload, and tongue weight limits.

Project what a vehicle will be worth in future years and how much value it loses each year.

Convert lumber dimensions to board feet and price a cut list, with nominal and actual sizes handled correctly.

Size heating and cooling for a room using area, climate, insulation, windows and occupancy.

Calculate cubic yards of concrete for slabs, footings, columns, and steps — including waste allowance and bag counts.

Estimate decking boards, joists, posts, fasteners, and total material cost for a deck build.

Work out sheets, joint compound, tape and screws for a room, with openings deducted.

Calculate posts, rails, pickets, concrete, and total cost for a fence run.

Calculate boxes of flooring, underlayment, and total cost including waste for cuts and pattern matching.

Calculate tons and cubic yards of gravel, crushed stone, or road base for a driveway or project area.

Work out how many cubic yards or bags of mulch you need for your beds, and what it will cost.

Calculate how many gallons of paint you need for walls, ceilings, and trim — accounting for doors, windows, and coats.

Estimate roofing squares, bundles, underlayment and cost from your footprint and roof pitch.

Calculate area for rectangles, circles, triangles, and irregular rooms — and convert between units.

Calculate rise, run, stringer length and headroom for a code-compliant staircase.

Calculate tiles, boxes, thinset and grout for a floor or wall, including diagonal layout waste.

Turn hydration, salt, and starter percentages into exact gram weights — with the flour and water inside your levain properly accounted for.

Swap one pan for another without a spill or a raw middle — see the batter depth and the time adjustment before it goes in.

Work out the salt for a wet or dry brine by weight, in grams and in cups of the specific salt sitting in your cupboard.

Get the coffee and water for any brew ratio and method, including how much you actually end up with in the cup.

Convert cups, spoons, and millilitres to grams for a specific ingredient — because a cup of flour and a cup of honey are nothing alike.

Estimate roasting time by weight, and see the temperature to pull at so carryover lands the meat exactly where you want it.

Convert between Fahrenheit, Celsius, and gas mark, and adjust for a fan oven that runs hotter than the dial says.

Scale any recipe up or down and get the new amounts in measurements you can actually use, not awkward decimals.

Convert a recipe between the oven, a slow cooker on low or high, and a pressure cooker without guessing.

Convert between bits and bytes, size a connection for concurrent users, and estimate monthly data transfer.

Convert between CIDR notation and subnet masks, and see how many addresses each prefix length provides.

Estimate monthly and annual cloud VM cost including storage, egress, reserved instance discounts, and auto-shutdown savings.

Calculate how long a file transfer will take at a given throughput, and the effective speed you actually achieve.

Calculate usable capacity after RAID, formatting overhead, and growth — plus cloud storage cost.

Estimate how long a transfer really takes at a given link speed, including protocol overhead and realistic efficiency.

Convert a start and end IP address into the CIDR blocks that cover it, and count the addresses in a range.

Explore IPv6 prefix sizes, subnet counts, and address space — and expand compressed addresses.

Calculate the correct MTU and TCP MSS for tunnels, VPNs, and overlay networks with encapsulation overhead.

Measure password strength in bits of entropy and see how long an offline attack would take at realistic cracking rates.

Estimate total system draw and the power supply size you should buy, with headroom for transients and efficiency.

Work out usable capacity, fault tolerance and efficiency for RAID 0, 1, 5, 6 and 10 before you buy the drives.

Calculate network address, broadcast, usable host range, wildcard mask, and host count from any IPv4 address and CIDR prefix.

Convert between dotted-decimal subnet masks, CIDR prefixes, wildcard masks, and binary — with host counts.

Convert an SLA percentage into the downtime it actually permits per day, month and year — and see what chaining dependencies does to it.

Compare two cities by cost index and find the salary you need to maintain the same standard of living.

Convert an hourly wage into annual, monthly, and weekly salary — including overtime and unpaid time off.

Compare two offers on total compensation — salary, bonus, equity, match, benefits and commute.

Work out how many months your savings, severance, and unemployment benefits will cover after a job loss.

Calculate overtime and double-time pay for a week, including the correct regular rate when a bonus is involved.

Track paid time off accrual per pay period, project your balance, and value your unused days in dollars.

Work out what a raise is worth per paycheck, and whether it actually beats inflation.

Convert an annual salary into an hourly, daily, weekly, and monthly rate — adjusted for paid time off.

Estimate a severance package, what it nets after tax, and how long it will actually last you.

Estimate net pay per paycheck after federal tax, FICA, state tax, retirement contributions, and benefit deductions.

Find the sales volume where you stop losing money, and how much further you have to go to hit a profit target.

Work out net burn, how many months of runway you have left, and the date the cash runs out.

Payment, total interest, and the true APR once the origination fee is counted — plus what the interest deduction actually saves you.

What a customer costs to win against what they are worth, and how long you wait to get the acquisition cost back.

Work backwards from the income you want to the hourly rate you have to charge, once unbillable time, expenses, and self-employment tax are taken out.

Add up line items, apply a discount and sales tax in the right order, and see the balance due after a deposit.

Convert between markup and margin, and find the price that hits the margin you actually want.

Project recurring revenue with churn and expansion, and find your net revenue retention and average customer lifetime.

Solve for price, cost, or margin — and stop confusing a 50% markup with a 50% margin, because they are not the same thing.

Return on investment, annualised so you can compare a six-month project against a three-year one honestly.

Model tiered or flat commission, quota attainment and accelerators to see real on-target earnings.

What a hire actually costs once payroll taxes, benefits, equipment, and paid time off are added to the salary.

Work out an exact age in years, months and days, plus total weeks, days and the next birthday.

Find the mean, median, mode, range and standard deviation of any list of numbers.

Count the days, weeks, months and business days between two dates — or add a duration to a date.

Find the sale price after one or more discounts, and check what a stacked offer is really worth.

Add, subtract, multiply and divide fractions, with the result simplified and shown as a decimal and percentage.

Every common percentage question in one place — what is X% of Y, X as a percentage of Y, and percentage change.

Simplify a ratio, scale it to a new total, or solve for the missing term in a proportion.

Add up hours and minutes, work out the time between two clock times, and convert to decimal hours for timesheets.

Work out the tip and split a bill between any number of people, with or without tax included.

Convert length, weight, volume, area, speed and data between metric and imperial units with exact factors.

Find what any appliance costs to run per hour, day, month and year at your own electricity rate.

Compare the total cost of an electric and a petrol car over your ownership period, not just the sticker price.

Compare annual heating cost and payback for a heat pump against gas, oil, propane or electric resistance.

Add up your whole home's electricity use appliance by appliance and see where the bill actually goes.

Estimate system size, production, savings and the year a solar installation pays for itself.

Project the full four-year cost of a degree with inflation, aid and the loan repayment that follows.

Work out exactly what you need on the final exam to reach the grade you want.

Calculate a weighted grade point average from your courses, and see what it takes to move it.

Convert marks to a percentage and letter grade, with or without a curve.

Convert your dog's age to human years using size-adjusted ageing, not the seven-year myth.

Estimate the true annual and lifetime cost of owning a pet, including the expenses people forget.

Work out daily calories and cup portions for a dog or cat based on weight, age and activity.