Convert any number to and from scientific notation, or calculate with two numbers in scientific notation — full working shown.
Scientific notation (also called standard form) writes a number as a coefficient between 1 and 10, multiplied by 10 raised to a power. It's used throughout science and engineering to express very large or very small numbers without writing out long strings of zeros.
To convert a standard number to scientific notation, move the decimal point until only one non-zero digit remains to its left, and count how many places you moved it — that count becomes the exponent. Moving the decimal left gives a positive exponent (for large numbers); moving it right gives a negative exponent (for small numbers).
To multiply two numbers in scientific notation, multiply the coefficients and add the exponents. To divide, divide the coefficients and subtract the exponents. Addition and subtraction are trickier — the exponents must first be made equal before the coefficients can be combined.
It keeps very large numbers (like the distance to a star) and very small numbers (like the mass of an atom) compact, readable, and easy to compare by simply looking at the exponent.
The "e" stands for "exponent" and is calculator/programming shorthand for "× 10^". So 4.5e5 means 4.5 × 10⁵, which equals 450,000.
This is the standard convention for scientific notation — it guarantees every number has exactly one unambiguous representation, making it easy to compare magnitudes just by reading the exponent.