Free online calculators for money, health, and everyday math

How to use this calculator

1. Enter your card balance. 2. Enter the APR from your statement. 3. Enter the days in your billing cycle (usually 28 to 31).

Worked example

$5,000 balance at 24.99% APR over a 30-day cycle: the daily rate is 0.0685%, interest is $102.70, and the new balance is $5,102.70.

How the math works

Daily periodic rate = APR / 365. Interest = balance x daily periodic rate x days in the cycle. That is the standard way issuers explain periodic interest.

How this calorie estimate works

The calculator first estimates basal metabolic rate, the energy your body uses at rest. It then multiplies that value by your chosen activity level to estimate total daily energy expenditure.

Use the result as a planning range

Long-term returns are uncertain. Compare a conservative rate with a more optimistic one and review the gap. A future dollar balance also buys less when inflation rises.

Total ROI and annualized return answer different questions

Total ROI shows the gain relative to the full cost basis. Annualized return converts the whole-period change into an average compounded yearly rate, making different holding periods easier to compare.

What a SIP projection shows

A systematic investment plan invests a fixed amount on a regular schedule. This projection separates the money invested from the estimated market growth.

नोट: यह केवल अनुमान है. वास्तविक रिटर्न बाजार के साथ बदलता है.

Progressive tax means each band is taxed separately

The highest rate reached does not apply to all income. The calculator subtracts the 2026 standard deduction, applies each ordinary-income bracket in order, then subtracts the credits entered.

Mercado en español: las búsquedas de calculadora de salario neto, ISR e IMSS son especialmente comunes en México. Esta versión calcula impuesto federal de Estados Unidos.

What a dividend growth projection shows

This projection simulates year-by-year compounding: the dividend per share grows at the entered rate, the share price grows at its own rate, and with DRIP on, each dividend buys more shares at that year's price. Any yearly additional investment buys shares at that year's price.

For context, the S&P 500 has returned about 10% per year over the long run before inflation. This calculator starts from each ETF's own history instead, and every rate stays adjustable - treat the past as a reference point, not a promise.

What the numbers mean

Download speed (Mbps) is how fast you pull data in - it decides stream quality and download times. Upload speed is how fast you send data out - it matters for video calls, live streaming, and cloud backups. Ping (ms) is round-trip delay - lower is better, and under 50 ms feels instant for gaming and calls.

As a rule of thumb: under 10 Mbps struggles with HD video, 10-25 Mbps handles HD streaming, 25-100 Mbps covers 4K and busy households, and 100+ Mbps is excellent for everything including competitive gaming.

Minimum vs recommended

Minimum specs will launch the game, usually at low settings and 30 frames per second. Recommended specs target smooth 60 fps play at high settings. If your PC sits between the two, expect a mix of medium settings.

The four parts that matter most are the CPU (processor), GPU (graphics card), RAM (memory), and free storage space - an SSD is strongly preferred for modern titles.

How to use this calculator

1. Enter the home price, your down payment, mortgage rate, and loan term under Buying. 2. Add ownership costs: property tax, insurance, HOA dues, and closing costs. 3. Enter a comparable monthly rent and how fast rents rise in your area. 4. Set the comparison length and your tax and investment assumptions. 5. Read the verdict, note the breakeven year, and compare the two cost lines on the chart.

Worked example

A $400,000 home with 20% down at 6.5% over 30 years, versus $2,200 per month rent rising 3% a year, over 10 years: buying costs about $98,960 in net terms while renting costs about $215,468. Buying saves roughly $116,508, with breakeven in year 2.

What this means and what to do next

If buying wins by a wide margin and you plan to stay past the breakeven year, ownership is the stronger financial move. If renting wins, or the breakeven sits beyond your likely stay, renting and investing the difference usually comes out ahead. Either way, re-run the numbers with your actual quotes before deciding.

How the math works

Each year, the buying side adds mortgage payments, property tax, insurance, and HOA dues, then subtracts the equity you built (appreciation plus principal repaid) and the tax savings on mortgage interest. The renting side adds rent and renter's insurance, then subtracts the investment growth on the down payment and closing costs you kept invested instead. The breakeven year is the first year buying's cumulative net cost drops below renting's.

How to use this calculator

1. Enter your current loan balance, interest rate, and remaining term. 2. Add a monthly extra payment, a one-time lump sum, or both. 3. Read the interest and time saved, your new payoff date, and compare the two balance lines on the chart.

Worked example

A $300,000 balance at 6.5% with 30 years left, plus $200 extra per month: you save about $103,449 in interest, finish 6 years and 11 months early, and pay off in Nov 2049 instead of Oct 2056. Total interest drops from about $382,633 to about $279,185.

How the math works

Each month, interest accrues on the remaining balance, then your regular payment plus any extra goes toward principal. Extra payments shrink the balance faster, so less interest accrues and the loan ends early. Interest saved is the total interest on the original schedule minus the total interest with extra payments.

How to use this calculator

1. Enter your gross annual income, monthly debt payments, and down payment. 2. Set the interest rate and loan term. 3. Read your max home price, your max monthly payment, and which rule set the limit.

Worked example

With $100,000 income, $500 in monthly debts, and an $80,000 down payment at 6.5% over 30 years: the 28% rule caps your payment at $2,333 per month, which supports a loan of about $369,159, for a max home price of about $449,159. The 36% back-end rule would allow $475,527, so the front-end rule is the binding limit.

How the math works

Monthly income is annual income divided by 12. The front-end rule allows 28% of it for housing; the back-end rule allows 36% minus your other monthly debts. The smaller of the two caps your monthly payment. That payment converts to a loan amount with the standard amortization formula, and your down payment is added to reach the max home price.

How to use this calculator

1. Enter your annual gross pay. 2. Pick your pay frequency. 3. Choose your filing status. 4. Add pre-tax deductions per paycheck, like 401(k) or HSA contributions. 5. Read your take-home pay per paycheck and the annual breakdown.

Worked example

A $75,000 salary paid biweekly with single filing and no pre-tax deductions: taxable income is $58,900 after the $16,100 standard deduction. Federal tax is $7,670 and FICA is $5,738, so annual take-home is $61,593 - about $2,369 per paycheck.

What this means and what to do next

If the take-home number surprises you, the biggest levers are pre-tax contributions and your W-4 withholding. This is federal only: subtract your state and local taxes for a fuller picture.

How the math works

Taxable income is gross pay minus pre-tax deductions times paychecks minus the standard deduction for your filing status. The 2026 federal brackets apply progressively to that amount. Then 6.2% Social Security on wages up to the $184,500 wage base and 1.45% Medicare on all wages are subtracted. Annual take-home divided by your number of paychecks gives per-paycheck pay. No state or local tax is modeled, and the extra 0.9% Medicare tax on wages over $200,000 is not included.

How to use this calculator

1. Enter your current loan balance, rate, and years remaining. 2. Enter the new rate, new term, and closing costs from your refinance quote. 3. Read your monthly savings, breakeven point, and lifetime interest savings.

Worked example

A $400,000 balance at 7.5% with 30 years left, refinanced at 6.0% for 30 years with $8,000 closing costs: the payment drops from $2,797 to $2,398, saving about $399 a month. Breakeven is 21 months, and lifetime interest savings net of closing costs are about $135,516.

What this means and what to do next

If the verdict says it is worth it and you plan to keep the loan past the breakeven point, refinancing usually pays off. If the breakeven sits beyond your likely stay or you might move soon, the closing costs are not recovered.

How the math works

Current and new payments use the standard amortizing loan formula. Breakeven is closing costs divided by monthly savings, rounded up. Lifetime interest savings is the remaining interest on your current loan minus the interest on the new loan and the closing costs.

How to use this calculator

1. Enter the first day of your last menstrual period. 2. Adjust the average cycle length if yours differs from 28 days. 3. Read the estimated due date, conception date, and current week.

Worked example

Last period started January 1, 2026, with a 28-day cycle: the estimated due date is October 8, 2026, and the estimated conception date is January 15, 2026.

How the math works

Naegele's rule adds 280 days (40 weeks) to the first day of the last period, then adjusts by the difference between your cycle length and 28 days. Gestational age counts from the period date, not conception, which is why pregnancy is described as 40 weeks even though conception happens about two weeks later.

How to use this calculator

1. Enter your current course grade. 2. Enter how much the final exam counts toward the grade. 3. Enter the final grade you want and read the exam score you need.

Worked example

Current grade 85%, final worth 30%, target 90%: you need 101.67% on the final, which is not possible. The best you can finish with is 89.5%.

How the math works

Needed score = (target - current x (1 - weight)) / weight. Your current grade already locks in part of the result; the final can only move the remaining weighted portion.

How to use this calculator

1. Enter what one item costs you. 2. Enter the price you sell it for. 3. Read the profit, the margin, and the markup.

Worked example

Cost $60, price $100: profit is $40.00, margin is 40.00% (40/100), and markup is 66.67% (40/60).

How the math works

Profit = price - cost. Margin = profit / price, which answers "what share of each sale do I keep?" Markup = profit / cost, which answers "how much do I add on top of cost?" Because price is bigger than cost, markup is always the larger number.

How to use this calculator

1. Enter sex, height, and tape measurements in inches. 2. Add your weight and a daily calorie target. 3. Adjust the protein, carb, and fat shares and read the gram targets.

Worked example

Male, 70 in tall, 16 in neck, 34 in waist, 180 lb, 2,000 calories at 30/40/30: body fat about 15.5%, fat mass about 27.9 lb, lean mass about 152.1 lb, with targets of 150 g protein, 200 g carbs, and 67 g fat.

How the math works

The US Navy formula estimates body fat from the relationship between waist, neck, and height (plus hips for women) using logarithms fitted to underwater-weighing data. Macro grams come from the calorie shares: protein and carbs provide 4 calories per gram, fat provides 9.

How to use this calculator

1. Enter the one-way trip distance. 2. Pick mpg or liters per 100 km and enter your efficiency. 3. Enter the fuel price and choose one way or round trip.

Worked example

300 miles at 30 mpg with gas at $3.50 per gallon, one way: 10 gallons for a total of $35.00. The same trip as a round trip doubles to $70.00.

How the math works

Fuel used = distance / efficiency for mpg, or distance x efficiency / 100 for liters per 100 km. Round trip doubles the distance first. Total cost = fuel used x price per unit.

How to use this calculator

1. Pick slab or footing. 2. Enter length, width, and thickness. 3. Keep the 10% waste allowance unless your forms are exact, then read cubic yards and bag counts.

Worked example

A 10 by 10 ft slab, 4 inches thick, with 10% waste: about 1.36 cubic yards (1.04 cubic meters), or 82 sixty-pound bags, or 62 eighty-pound bags.

How the math works

Volume = length x width x thickness (converted to feet), divided by 27 for cubic yards. The waste percentage pads the result for spillage and uneven subgrade. A 60 lb bag yields about 0.45 cubic feet and an 80 lb bag about 0.6 cubic feet, so bags = volume / yield, rounded up.

How to use this checker

1. Type any website address and press Check now. 2. A green Up means the server answered; a red Down means nothing answered within 15 seconds. 3. Use the popular-sites board to test big sites one by one, or press Check all.

Worked example

Checking google.com usually returns Up in well under a second. Checking a made-up address like this-site-does-not-exist-12345.com returns Down or unreachable, because no server answers.

How the check works

Your browser sends a lightweight request to the address with a 15 second timeout and measures how long the server takes to answer. The request runs in a mode that hides the exact HTTP status code, so the answer is reachable or unreachable - not 200 versus 404 versus 500. The check runs entirely in your browser; nothing is sent to CrunchBench.

How to use this calculator

1. Enter the first day of your last period. 2. Enter your average cycle length in days. 3. Read your estimated ovulation day, fertile window, and next period date.

Worked example

With a last period starting January 1, 2026 and a 28-day cycle, ovulation falls around January 15, 2026, the fertile window runs January 10 through January 15, and the next period is estimated around January 29.

How the math works

Ovulation usually happens about 14 days before the next period, so ovulation day = last period start + (cycle length - 14) days. The fertile window covers the 5 days before ovulation plus ovulation day itself, since sperm can survive up to 5 days.

How to use this calculator

1. Enter the home price. 2. Enter your down payment as a percent of the price. 3. Read the closing cost range, your down payment in dollars, and the total cash needed to close.

Worked example

On a $400,000 home with 10% down, the down payment is $40,000, closing costs run about $8,000 to $20,000, so plan on $48,000 to $60,000 in total cash to close.

How the math works

Closing costs typically run 2% to 5% of the home price. Down payment = price x down payment percent. Cash to close = down payment + closing costs. The itemized lines use typical averages: 1% loan origination, 0.75% title insurance, and 1% prepaid taxes and insurance.

How to use this calculator

1. Enter your gross monthly income before taxes. 2. Enter each monthly debt payment. 3. Read your back-end and front-end DTI ratios.

Worked example

With $8,000 of monthly income and $2,700 in debts ($2,000 housing + $400 auto + $200 cards + $100 other), back-end DTI is 33.8% and front-end DTI is 25.0%, leaving $5,300 after debts.

How the math works

Back-end DTI = total monthly debt payments / gross monthly income x 100. Front-end DTI = housing payment / gross monthly income x 100. Only minimum required debt payments count; utilities, groceries, and taxes are excluded.

How to use this calculator

1. Enter both fractions. 2. Pick the operation. 3. Read the simplified fraction, its decimal, and the steps.

Worked example

1/2 + 1/3 = 3/6 + 2/6 = 5/6, which is 0.8333 as a decimal.

How the math works

Addition and subtraction use a common denominator: a/b + c/d = (ad + bc) / bd. Multiplication multiplies straight across: a/b x c/d = ac / bd. Division flips the second fraction: a/b ÷ c/d = ad / bc. The result is reduced by dividing numerator and denominator by their greatest common divisor (GCD).

How to use this calculator

1. Enter your total fixed costs. 2. Enter the selling price and variable cost per unit. 3. Read the units and revenue needed to break even.

Worked example

With $10,000 in fixed costs, a $50 price, and a $30 variable cost, each unit contributes $20.00, so you break even at 500 units and $25,000 in revenue.

How the math works

Contribution margin = price - variable cost per unit. Break-even units = fixed costs / contribution margin, rounded up. Break-even revenue = break-even units x price. Price must exceed variable cost, or you never break even.

How to use this calculator

1. Enter the home price and both loan rates. 2. Pick each loan term. 3. Compare the piggyback payment against a single 95% loan with PMI.

Worked example

On a $600,000 home at 6.5% for 30 years on the first loan and 8.0% for 30 years on the second: the $480,000 first loan costs $3,033.93/month and the $90,000 second costs $660.39/month, for $3,694.31 combined with $30,000 down. A single $570,000 loan at 6.5% plus ~$237.50 PMI totals $3,840.29, so the piggyback saves $145.97 per month.

How the math works

An 80-15-5 splits the purchase into an 80% first mortgage, a 15% second mortgage, and a 5% down payment, avoiding PMI because no loan exceeds 80% of the price. Monthly payments use standard amortization: P x r(1+r)^n / ((1+r)^n - 1) with r = annual rate / 12. The comparison prices a single 95% loan at the first-loan rate plus PMI estimated at 0.5% of the loan per year / 12.

How to use

1. Enter your yearly deposit (up to ₹1,50,000). 2. Adjust the interest rate if it has changed. 3. Set the tenure in years and read the maturity value.

Worked example

Depositing ₹1,50,000 each year at 7.1% for 15 years gives a maturity value of ₹40,68,209: ₹22,50,000 invested and ₹18,18,209 earned as interest.

How the math works

Annual compounding with deposits at the start of each year: maturity = D x (((1+r)^n - 1) / r) x (1+r), where D is the yearly deposit, r the annual rate, and n the years. The extra (1+r) factor is the start-of-year deposit bonus.

How to use

1. Enter your monthly basic salary plus dearness allowance. 2. Enter your completed years of service. 3. Read the gratuity payable.

Worked example

Basic + DA of ₹50,000 with 10 years of service: 50,000 x 15/26 x 10 = ₹2,88,462 payable as gratuity.

How the math works

Gratuity = monthly basic x 15/26 x years of service. The 15/26 factor treats a month as 26 working days and pays 15 days of wages for each year of service.

How to use

1. Enter your gross annual income. 2. Enter your 80C, 80D, and HRA figures (old regime only). 3. Compare both taxes and pick the cheaper regime.

Worked example

₹15L income with ₹1.5L 80C and ₹25k 80D: old regime tax is ₹2,02,800, new regime tax is ₹97,500. The new regime wins and saves ₹1,05,300.

How the math works

Old regime: taxable = gross - 80C - 80D - HRA - ₹50k standard deduction; slabs of 5%/20%/30% above ₹2.5L with nil tax up to ₹5L under 87A. New regime: taxable = gross - ₹75k standard deduction; slabs of 5% to 30% above ₹4L with nil tax up to ₹12L under 87A. Both add 4% health and education cess.

How to use

1. Enter monthly basic + DA and the total contribution rate (usually 24%). 2. Enter your current balance and years left. 3. Read the projected corpus.

Worked example

Basic of ₹50,000 at 24% monthly contribution, ₹5,00,000 balance, 20 years at 8.25%: a corpus of ₹98,80,755 from ₹33,80,000 contributed and ₹65,00,755 earned as interest.

How the math works

Monthly compounding: corpus = balance x (1+i)^n + PMT x (((1+i)^n - 1)/i), where PMT is the monthly contribution, i the monthly rate, and n the months left. Contributions are basic x contribution rate.

How to use

1. Enter monthly basic, HRA received, and rent paid. 2. Pick metro or non-metro. 3. Read the exempt and taxable amounts.

Worked example

Basic ₹60,000, HRA ₹30,000, rent ₹25,000 in a metro city: exempt is the minimum of ₹3,60,000, ₹2,28,000, and ₹3,60,000, so ₹2,28,000 is exempt and ₹1,32,000 is taxable.

How the math works

Exempt HRA = minimum of three annual amounts: HRA received, rent paid minus 10% of basic salary, and 50% of basic (metro) or 40% (non-metro). The rest of your HRA is taxable.

How the math works

ISR: the 2026 monthly tariff (Art. 96 LISR) is applied to your gross salary. For example, $20,000 falls in the $17,533.65-$35,362.83 bracket: 21.36% on the excess over $17,533.65 plus $1,856.84 fixed = $2,383.65.

Subsidio al empleo: $535.65/month applies when gross income is up to $11,492.66. It reduces ISR to zero but is never paid out in cash.

IMSS (employee): 1.125% cesantia y vejez + 0.625% invalidez y vida + 0.375% gastos medicos pensionados + 0.25% prestaciones en dinero + 0.40% enfermedad y maternidad (only on the amount exceeding 3 UMA daily).

Tax tables verified: October 2026. Sources: SAT (Anexo 8, RMF 2026), IMSS (LSS Arts. 106-108, 147, 168).