Math calculator

Free scientific notation calculator

Express any number in scientific notation — enter a standard or scientific notation number to convert it instantly, updated live, as you type.

InputsLive
Number
Significant Figures
Number of significant figures to display (default 4)
Result
Scientific notation
1.235 × 10^8
123456789 = 1.235 × 10^8
Mantissa1.234568
Exponent8
Sig Figs4
Original Number123456789

Result shown as mantissa × 10^exponent form. Uses IEEE 754 double precision.

Results are estimates. Consult a professional.

How it's calculated

How the scientific notation calculator works

Scientific notation expresses any number as a coefficient multiplied by a power of ten: a × 10ⁿ. The coefficient a must satisfy 1 ≤ |a| < 10 — exactly one non-zero digit before the decimal point. To convert, move the decimal point until that condition is met and count the moves: each move left increases n by 1; each move right decreases it by 1.

Standard form: a × 10ⁿ where 1 ≤ |a| < 10
Large number: move decimal LEFT → n is positive
Small number: move decimal RIGHT → n is negative
n = number of places moved (+ for left, for right)
Scientific notation follows the conventions in NIST SP 811 and the SI Brochure for expressing measurements across many orders of magnitude.
Example

Worked example: 0.000456 and 3,200,000

Example: a very small and a very large number

Convert 0.000456 (a small decimal) and 3,200,000 (a large integer) into scientific notation to show both directions.

0.000456: move decimal 4 places RIGHT to get 4.56
→ 4.56 × 10⁻⁴
3,200,000: move decimal 6 places LEFT to get 3.2
→ 3.2 × 10⁶
4.56 × 10⁻⁴
0.000456 = 4.56 × 10⁻⁴. And 3,200,000 = 3.2 × 10⁶.
Quick reference

Common scientific measurements in scientific notation

Science and engineering use scientific notation to handle measurements that span dozens of orders of magnitude without cumbersome strings of zeros.

QuantityValueScientific notation
Speed of light (m/s)299,792,458≈ 3.0 × 10⁸
Electron mass (kg)0.0000000000000000000000000000009119.109 × 10⁻³¹
Earth's mass (kg)5,972,000,000,000,000,000,000,0005.972 × 10²⁴
Avogadro's number (mol⁻¹)602,214,076,000,000,000,000,0006.022 × 10²³
Proton mass (kg)0.000000000000000000000000001672621.673 × 10⁻²⁷
Diameter of hydrogen atom (m)0.0000000001061.06 × 10⁻¹⁰
Distance Earth–Sun (m)149,600,000,0001.496 × 10¹¹
Planck's constant (J·s)0.0000000000000000000000000000000006636.626 × 10⁻³⁴

Source: NIST CODATA 2018 recommended values of fundamental physical constants.

Practical tips

Tips for working with scientific notation

Scientific notation is required in chemistry, physics, astronomy, and engineering. These habits prevent the most common errors.

  • Keep exactly one digit before the decimal — 12.5 × 10³ is not standard form; rewrite as 1.25 × 10⁴ by moving the decimal one place left and increasing the exponent by 1.
  • Multiplying in scientific notation — Multiply the coefficients, then add the exponents: (3 × 10⁴) × (2 × 10³) = 6 × 10⁷. Adjust if the coefficient exceeds 10.
  • Dividing in scientific notation — Divide the coefficients, subtract the exponents: (8 × 10⁶) ÷ (4 × 10²) = 2 × 10⁴.
  • Adding/subtracting requires matching exponents — Convert both numbers to the same power of ten before adding or subtracting the coefficients.
  • Significant figures travel with the coefficient — 3.20 × 10⁵ has three significant figures; 3.2 × 10⁵ has two. The exponent does not affect significant-figure count.
Accuracy & limits

Accuracy and limitations

The conversion between standard decimal and scientific notation is exact — it is purely a change of representation, not a calculation. The number of significant figures displayed is determined by how many digits you enter: trailing zeros in the coefficient are significant. For calculations that chain multiple scientific-notation values, rounding errors accumulate in the least-significant digits of the coefficient; retain extra digits in intermediate steps.

Glossary

Key terms

A way of expressing numbers as a × 10ⁿ where 1 ≤ |a| < 10. Used to compactly represent very large or very small quantities.
The number a in a × 10ⁿ. Must have exactly one non-zero digit to the left of the decimal point in standard form.
The integer n in a × 10ⁿ. Positive for large numbers; negative for numbers between 0 and 1. Indicates how many places the decimal has moved.
The meaningful digits in a measurement. In 3.20 × 10⁵, all three digits (3, 2, 0) are significant.
A variant where the exponent is always a multiple of 3, aligning with SI prefixes (kilo, mega, giga, milli, micro, nano, etc.).
A factor of 10. Two numbers that differ by an order of magnitude differ by a factor of 10; ten orders of magnitude is a factor of 10,000,000,000.
About

About this calculator

Part of our math calculators suite — explore all calculators.

Questions

Frequently asked questions about the free scientific notation calculator

A scientific notation calculator is a free online tool that helps you express any number in scientific notation form. n = mantissa × 10^exponent. It runs entirely in your browser with instant results and no sign-up.
JavaScript double-precision floating-point — accurate to about 15-17 significant digits. For arbitrary precision, use the Big Number calculator.
The statistics calculator computes population variance (divides by n). For sample variance, multiply variance by n/(n-1).

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