USA calculators are tools set up for the way money, work, school and measurement work in the United States: dollars, miles, pounds, Fahrenheit and US rules. These free USA calculators cover mortgages, retirement limits, overtime, sales tax, GPA and conversions, and show every step.
Quick answer: Most USA calculators start from a few US rules. Overtime is 1.5 times the regular rate after 40 hours in a workweek, the 2026 limits are $24,500 for a 401(k) and $7,500 for an IRA, and a 4.0 GPA scale runs A = 4, B = 3, C = 2. For example, 45 hours at $20 an hour pays 800 + 150 = $950.
How to use these USA calculators
Each of the USA calculators opens with a realistic US example, so you see an answer before you type anything. Prices are in dollars, lengths in feet and inches, and weights in pounds unless you change the unit.
- Choose the calculator from the decision table below or from the cards above.
- Type your own numbers. Rates such as a mortgage rate are editable examples, not quotes.
- Read the answer, then open the working to see the formula and your numbers in it.
- Copy the result or the link, or reset and try another scenario.
Nothing is sent to a server, so these USA calculators are safe for private numbers such as pay and loan balances. Results are estimates for planning, not tax, legal or financial advice.
Which USA calculator do I need? A quick decision table
This table matches common US questions to the right tool among the USA calculators. The link text names each calculator, so you can scan for your own question and open the USA calculator that fits it.
| If you want to… | Use this calculator |
|---|---|
| Estimate a monthly house payment with taxes, insurance and PMI | Mortgage calculator |
| Compare car or personal loan payments | Car loan calculator or Loan calculator |
| See what a 401(k) or IRA could grow to | Retirement calculator or Compound interest calculator |
| Pay off a credit card faster | Credit card payoff calculator |
| Turn an hourly wage into a yearly salary | Hourly to salary calculator |
| Pay time and a half or double time | Overtime calculator |
| Add sales tax, a tip or a discount | Tip, discount and sales tax calculator |
| Price a product with a markup | Markup calculator |
| Work out a GPA or the final exam score you need | GPA calculator or Final grade calculator |
| Count business days around federal holidays | Business days calculator |
| Check BMI in pounds and inches | BMI calculator |
| Convert miles per gallon, cups or Fahrenheit | MPG calculator, Cups to grams converter or Temperature converter |
| Estimate concrete, mulch or paint in cubic yards and gallons | Concrete calculator, Mulch calculator or Paint calculator |
| Find the square footage of a room | Square footage calculator |
US financial calculators: mortgage, loans and retirement
US financial calculators share one set of formulas, and the USA calculators add a few local details: 30-year fixed mortgages, PMI, escrow and tax-advantaged retirement accounts. The mortgage and loan tools use the standard payment formula M = L × r ÷ (1 − (1 + r)−n).
Mortgage calculator USA: payment, PMI and taxes
A mortgage calculator USA setting assumes monthly compounding and a 30-year fixed loan. A $400,000 home with 20% down is a $320,000 loan, and at 6.5% the principal and interest payment is $2,022.62 a month. With a down payment under 20%, lenders usually add private mortgage insurance (PMI) until the balance falls to 80% of the home value.
Property tax and insurance are then added to the payment, which lenders often collect in escrow. The mortgage calculator includes all of these and shows an amortization table. The Freddie Mac survey is a good place to compare your rate with the national average.
Rates move the payment more than most people expect. On the same $320,000 loan, every extra point of interest adds roughly $200 to $220 a month, which is why the USA calculators let you test several rates side by side.
Car loans, personal loans and credit cards
For vehicles, the car loan calculator adds trade-in value, sales tax and fees to the price before it works out the payment. For other borrowing, the loan calculator shows total interest and the payoff date, and the credit card payoff calculator shows how long a balance lasts with a fixed payment. Use the same loan amount and term for each offer, and compare total interest, not only the monthly figure.
401(k) and IRA limits for 2026
The retirement calculator takes your balance, monthly saving, return and inflation, so it helps to know the yearly limits. These are the 2026 figures from the IRS.
| Account (2026) | Contribution limit | Extra if you are 50 or older |
|---|---|---|
| 401(k), 403(b) and most 457 plans | $24,500 | $8,000 catch-up (total $32,500) |
| Traditional or Roth IRA | $7,500 | $1,100 catch-up |
Social Security is the other piece of US retirement income. Benefits can start as early as age 62, and waiting raises the monthly amount, so enter your own estimate from your Social Security statement in the other income box.
US tax calculators: sales tax, tips and discounts
US tax calculators handle a country with no single sales tax. The United States has no national sales tax. States, and often cities and counties, set their own rates, and five states have no statewide sales tax: Alaska, Delaware, Montana, New Hampshire and Oregon. That is why the tax rate is always a box you fill in on these USA calculators.
Example: a $50 item at an 8% combined rate adds $4, so the total is $54. A 30% discount on an $80 jacket takes $24 off, leaving $56, and 8% tax on that is $4.48, for $60.48. For a restaurant bill of $60, an 18% tip is $10.80. The tip, discount and sales tax calculator handles all three in one place and can split a bill between people.
US tax calculators for income tax depend on filing status, state and deductions, so use the IRS tools for a return. Our markup and loan tools cover the pricing and borrowing side. Compare with the VAT calculator if you ever price for a UK or EU customer, and see the other country hubs for local rules.
US salary calculator: hourly pay, overtime and minimum wage
A US salary calculator turns an hourly wage into yearly pay using 2,080 hours, which is 40 hours for 52 weeks. At $25 an hour that is $52,000 a year, $4,333.33 a month or $2,000 every two weeks. The hourly to salary calculator also converts salary back to an hourly rate. The federal minimum wage is $7.25 an hour, and many states set a higher rate.
Under the Fair Labor Standards Act, covered non-exempt employees must be paid at least time and one-half their regular rate for hours over 40 in a workweek. The overtime calculator applies that rule. California adds daily overtime after 8 hours and double time after 12.
| Hours in the week | Regular pay at $20 | Overtime pay at $30 | Total |
|---|---|---|---|
| 35 | $700.00 | $0.00 | $700.00 |
| 40 | $800.00 | $0.00 | $800.00 |
| 45 | $800.00 | $150.00 | $950.00 |
| 50 | $800.00 | $300.00 | $1,100.00 |
| 55 | $800.00 | $450.00 | $1,250.00 |
| 60 | $800.00 | $600.00 | $1,400.00 |
US GPA calculator: the 4.0 scale and weighted grades
A US GPA calculator multiplies each course grade point by its credits and divides by total credits. A 4 credit A, a 3 credit B and a 3 credit A earn 16 + 9 + 12 = 37 points over 10 credits, a 3.7 GPA. Many schools use plus and minus values such as A− at 3.7, so check your own scale. Use the GPA calculator for the plain 4.0 scale, the weighted grade calculator when assignments carry different weights, and the final grade calculator to find the exam score you need.
| Letter grade | Common percent range | Grade points |
|---|---|---|
| A | 90 to 100 | 4.0 |
| B | 80 to 89 | 3.0 |
| C | 70 to 79 | 2.0 |
| D | 60 to 69 | 1.0 |
| F | Below 60 | 0.0 |
Ranges and plus or minus cut-offs differ by school, so treat this as the common pattern. AP and honors courses often add a point in a weighted GPA, and each school sets its own rule.
US units: gallons, miles, Fahrenheit and cups
The US customary system is why conversion calculators matter. A US gallon is 3.785 liters, and 25 miles per US gallon is 9.41 liters per 100 km. A US customary cup is 236.588 mL, though nutrition labels use a legal cup of 240 mL, and a US tablespoon is 14.79 mL. The MPG calculator and cups to grams converter handle these, and 350°F is 176.7°C.
| Measure | US unit | Metric equal |
|---|---|---|
| Volume of fuel | 1 gallon | 3.785 liters |
| Cup (customary) | 1 cup | 236.588 mL |
| Tablespoon | 1 tablespoon | 14.79 mL |
| Temperature | 350°F | 176.7°C |
| Fuel economy | 25 mpg | 9.41 L/100 km |
Dates, holidays and time zones in the US
Federal agencies observe 11 holidays a year, including Juneteenth and Columbus Day, and business-day counts usually skip them. The business days calculator lets you add extra days off. Daylight saving time runs from the second Sunday in March to the first Sunday in November, which is March 8 to November 1 in 2026, and Hawaii and most of Arizona do not observe it. The time zone converter applies those dates automatically.
BMI in pounds and inches
The US BMI formula is 703 × pounds ÷ inches². At 5 ft 10 in (70 inches) and 170 pounds that is 24.4, inside the 18.5 to 24.9 range the CDC lists as healthy weight. BMI is a screen, not a diagnosis. The BMI calculator also shows the healthy weight range for any height.
Home and DIY in feet, cubic yards and gallons
US building materials are sold by the cubic yard, the bag and the gallon. A 10 ft by 10 ft slab 4 inches thick needs 1.23 cubic yards of concrete, and 200 square feet of mulch at 3 inches deep needs 1.85 cubic yards. A 12 ft by 10 ft room with 8 ft walls has 352 square feet of wall, about one gallon of paint per coat at 350 square feet a gallon. Start with the concrete calculator and mulch calculator, then use the square footage calculator for the room itself.
Real-life uses for USA calculators
- Buying a home. Run the mortgage at three rates and two down payments before you visit a lender, so you know what the USA calculators say your budget can carry.
- Starting a job. A $22 an hour offer is $45,760 over 2,080 hours, and a week with 45 hours pays $1,045 once time and a half is counted.
- College. Track a semester GPA and the final exam score you need, then print matching practice sheets from the math worksheets.
- Road trips. At 25 mpg, 300 miles uses 12 gallons, and at $3.50 a gallon the fuel costs $42.
- Weekend projects. Order concrete by the cubic yard and paint by the gallon, with 10% extra for waste.
Key terms for USA calculators
| Term | Meaning |
|---|---|
| PMI | Private mortgage insurance, usually charged when the down payment is under 20% |
| Escrow | An account where the lender collects property tax and insurance with your payment |
| 401(k) | An employer retirement plan with a yearly pre-tax or Roth limit |
| FLSA | The Fair Labor Standards Act, which sets federal overtime and minimum wage |
| Non-exempt | An employee who must be paid overtime for hours over 40 |
| GPA | Grade point average on a 4.0 scale, weighted by credits |
Questions people ask about US calculators
Is there a free US tax calculator?
Yes. For sales tax, tips and discounts, use the tip, discount and sales tax calculator. For income tax on a return, the IRS offers its own tools, because the result depends on filing status, state and deductions that a general tool cannot know.
How do I use a US salary calculator?
Enter your hourly rate, hours per week and weeks per year. The standard full-time year is 40 hours for 52 weeks, 2,080 hours, so $25 an hour is $52,000. Unpaid weeks or part-time hours change the total, so edit them to match your job.
Which mortgage calculator should I use for the USA?
Use a mortgage calculator that includes property tax, insurance, HOA fees and PMI, not only principal and interest. That total is what a US lender calls PITI, and it is the payment you will actually make each month.
Frequently asked questions
9 quick answers
What are USA calculators?
USA calculators are tools that use United States rules, units and currency: dollars, miles, pounds, Fahrenheit, US overtime law, US retirement accounts and the 4.0 GPA scale. They show the formula and the working for each result.
Is there a sales tax calculator for every US state?
One tool covers every state because you type the combined rate. The United States has no national sales tax, states and localities set rates, and five states have no statewide sales tax: Alaska, Delaware, Montana, New Hampshire and Oregon.
What are the 401(k) and IRA limits for 2026?
For 2026 the IRS limit is $24,500 for a 401(k) and $7,500 for an IRA. People aged 50 or older can add an $8,000 catch-up to a 401(k) and $1,100 to an IRA.
How is overtime calculated in the US?
Under federal law, non-exempt employees get at least 1.5 times their regular rate for hours over 40 in a workweek. At $20 an hour, 45 hours pays 40 × $20 + 5 × $30 = $950.
What is the federal minimum wage?
The federal minimum wage is $7.25 an hour, according to the US Department of Labor. Many states and cities set a higher rate, and employers must pay the higher of the two.
How do I calculate a GPA on the US 4.0 scale?
Multiply each grade point by the course credits, add the results and divide by total credits. A 4 credit A, a 3 credit B and a 3 credit A give 37 points over 10 credits, which is 3.7.
How much is a $400,000 mortgage payment?
A $320,000 loan, which is 20% down on a $400,000 home, costs $2,022.62 a month in principal and interest at 6.5% over 30 years. Taxes, insurance and PMI are extra.
Do the calculators use miles and gallons?
Yes, US units are the default: miles, US gallons, feet, pounds and Fahrenheit. You can switch to metric, and the MPG calculator converts to liters per 100 km.
Are the 2026 rates current?
The IRS limits and the federal minimum wage were checked in October 2026. Mortgage and loan rates are editable examples, so type the rate from your own quote.
Related calculators and country hubs
- Main hub: all free online calculators
- Other countries: Canada calculators, UK and Europe calculators, Australia calculators
- Most used in the US: mortgage calculator, overtime calculator, GPA calculator, percentage calculator
- Practice: money worksheets and math worksheets
Sources and further reading
- IRS: 2026 401(k) and IRA limits
- US Department of Labor: overtime pay
- US Department of Labor: minimum wage laws
- OPM: federal holidays
- Wikipedia: sales taxes in the United States
Last updated: October 2026.