Move the decimal point until exactly one nonzero digit remains to its left, then count the places moved. Moving left gives a positive exponent (6,500,000 = 6.5 × 10⁶); moving right gives a negative one (0.00045 = 4.5 × 10⁻⁴). Type any decimal into the Convert tab and the calculator shows the scientific and E-notation forms instantly.

E-notation is the computer-friendly version of scientific notation where 'e' means 'times ten to the power of'. So 3.5e-4 means 3.5 × 10⁻⁴ = 0.00035, and 6.5E6 means 6.5 × 10⁶ = 6,500,000. The calculator accepts both formats as input, including the caret style 3.5 × 10^-4.

For multiplication, multiply the coefficients and add the exponents: (2 × 10³) × (3 × 10⁴) = 6 × 10⁷. For division, divide the coefficients and subtract the exponents. If the resulting coefficient falls outside 1–10, the calculator renormalizes it — for example 50 × 10⁵ becomes 5 × 10⁶.

Addition and subtraction only work on like terms, so both numbers must share the same power of ten first. To compute 4.2 × 10⁵ + 3 × 10⁴, rewrite the second as 0.3 × 10⁵, giving 4.5 × 10⁵. The calculator handles this alignment automatically in Calculate mode.

Yes. It is free, requires no sign-up, and all conversion and arithmetic runs entirely in your browser — nothing is transmitted to a server. It works on phones and tablets, which makes it handy for chemistry, physics, and astronomy homework anywhere.