Petameter to Attometer

The attometer is an extremely small unit of length equal to 10⁻¹⁸ meters, or one quintillionth of a meter.

1 am = 10⁻¹⁸ m = 10⁻⁹ nm = 0.001 fm. One meter contains 10¹⁸ attometers.

To convert am to meters: multiply by 10⁻¹⁸. To convert meters to am: multiply by 10¹⁸.

Measuring quark interaction distances and the scale of fundamental particle phenomena.

The effective size of a quark is estimated at less than 1 attometer — far smaller than a proton (~1,000 am across).

Confusing attometers with angstroms (Å = 10⁻¹⁰ m). Attometers are 100 million times smaller than an angstrom.

Think of the prefix chain: milli (10⁻³), micro (10⁻⁶), nano (10⁻⁹), pico (10⁻¹²), femto (10⁻¹⁵), atto (10⁻¹⁸).