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Online Calculator

By Bruno Tonetto · Reviewed on · How we verify

A free online scientific calculator that solves whole expressions — powers, roots, trig, factorials, percentages and averages — right in the browser. Instead of pressing one button at a time, you type the expression and the result updates as you type. It also speaks spreadsheet: the Excel-style financial functions (PMT, PV, FV, RATE, NPER, NPV) work here too.

How to type an expression

Write the math the way you would on paper. The calculator follows the order of operations (exponents first, then multiplication and division, then addition and subtraction) and you can group with parentheses. Use the decimal point (1.5) and the comma to separate function arguments, as in max(3, 7, 2) — exactly like a US spreadsheet.

Operators

Functions and constants

Worked examples

Real use cases, by category. Tap ▶ try it on any example to send the expression to the calculator above and see the result.

Grocery bill (items × quantities)4.99+12.50+3*2.89+2*6.75 → 39.66
Price with 8% sales tax59.99*108% → 64.79
Price with 25% off79.99*(100-25)% → 59.99
Splitting the bill 4 ways142.80/4 → 35.70
What's left from the paycheck2400-950-320-180-260 → 690
Rule of three (3 units cost 120; 5 cost?)120/3*5 → 200
What is 18% of 25018%*250 → 45
Increase 250 by 18%250*118% → 295
Decrease 250 by 18%250*82% → 205
What percent is 320 of 800320/800*100 → 40
Change from 910 to 1230 (%)(1230-910)/910*100 → 35.16
Margin: cost 60, price 100 (%)(100-60)/100*100 → 40
Compound interest: $10,000 at 0.4% a month for 24 months10000*(1+0.4%)^24 → 11,005.48
Future value (FV) equivalentFV(0.4%, 24, 0, -10000) → 11,005.48
$10,000 at 5% a year for 10 years10000*(1+5%)^10 → 16,288.95
Present value (PV): $200/month for 12 months at 0.4%PV(0.4%, 12, -200) → 2,338.75
Rule of 72 (years to double at 5% a year)72/5 → 14.40
Real return (5% nominal, 2.5% inflation) in %((1+5%)/(1+2.5%)-1)*100 → 2.44
Car payment (PMT): $30,000, 60 months at 7% APRPMT(7%/12, 60, -30000) → 594.04
Total paid over the loanPMT(7%/12, 60, -30000)*60 → 35,642.16
Payment on $5,000 over 24 months at 1.5% a monthPMT(1.5%, 24, -5000) → 249.62
Interest cost of 12×$89 for a $1,000 phone89*12-1000 → 68
How much can I borrow with a $500 payment? (48 months, 7% APR)PV(7%/12, 48, -500) → 20,880.10
Power: 2 to the 10th2^10 → 1,024
Square root of 2sqrt(2) → 1.4142
Hypotenuse (legs 3 and 4)sqrt(3^2+4^2) → 5
Area of a circle (radius 5.7)pi*5.7^2 → 102.07
Factorial of 66! → 720
Volume of a sphere (radius 3)4/3*pi*3^3 → 113.10
Sine of 30° (π/6)sin(pi/6) → 0.50
Cosine of 60°cos(60*pi/180) → 0.50
Tangent of 45°tan(45*pi/180) → 1.00
Log base 10 of 1,000log(1000) → 3
Natural log of eln(e) → 1
e to the 2ndexp(2) → 7.3891

Frequently asked questions

Is this online calculator free?

Yes. It is 100% free, runs right in the browser (phone or computer) and needs no sign-up. The math happens on your own device, in real time.

Can I type 1,234.56?

Type numbers without the thousands separator: 1234.56. Here the comma separates the arguments of a function, as in max(3, 7, 2) — the same convention as Excel in the US — so a comma inside a plain number would be ambiguous and is rejected instead of silently guessed.

What is -2^2?

On this calculator the answer is 4: the minus sign binds to the 2 before squaring, i.e. (−2)². If you want −(2²) = −4, write -(2^2). Use parentheses whenever you want the intent to be unambiguous.

Do the trig functions use degrees or radians?

Radians. To work in degrees, convert by multiplying by pi/180 — the sine of 30° is sin(30*pi/180) or, equivalently, sin(pi/6).

What does the % after a number mean?

The percent sign divides the value by 100. So 10% is 0.1, and 200*15% computes 15% of 200, which is 30.

The calculator evaluates the expression you type, following the order of operations. The 8% sales tax in the examples is illustrative — rates vary by state and city — and so is the 2.5% inflation. Double-check important numbers before making decisions.