Scientific Notation Calculator & Converter

Scientific notation writes very large and very small numbers as a number between 1 and 10 times a power of ten: 123,450,000 becomes 1.2345 × 10⁸ and 0.00052 becomes 5.2 × 10⁻⁴. This calculator converts any number into scientific, E and engineering notation (with the SI prefix) and back to ordinary digits, and it can add, subtract, multiply and divide two numbers written in scientific notation. The digits are handled as exact text, so even 10¹⁰⁰⁰ stays precise.

How to use this tool

1. Type a number as plain digits (123450000), E notation (1.2345e8) or with ×10^ (1.2345×10^8).
2. For arithmetic, switch the mode, choose the operation and enter the second number.
3. Optionally set the number of significant figures to round to.
4. Copy whichever form you need — scientific, E, engineering or standard.

Formula

N = a × 10ⁿ, where 1 ≤ |a| < 10 · (a × 10ᵐ)(b × 10ⁿ) = ab × 10^(m+n)

The exponent n counts how many places the decimal point moves: left for big numbers (positive n), right for small ones (negative n). Engineering notation uses only exponents that are multiples of 3, matching SI prefixes such as kilo (10³), mega (10⁶) and micro (10⁻⁶). To add or subtract, the numbers are first written with the same power of ten.

Example

123,450,000 = 1.2345 × 10⁸ (E notation 1.2345e8, engineering 123.45 × 10⁶ or 123.45 mega). Multiplying (3 × 10⁵) × (2 × 10⁻³) gives 6 × 10², which is 600 in standard form.