The prefix ladder
Drag the bead along the ladder. Each coloured band covers three decades (×1000 from the band next to it), and the value under the bead is always written in the band’s prefix so that 1 ≤ mantissa < 1000.
Engineering notation
1 Hz
Drag the bead — or click anywhere on the ladder. Each small tick is one decade (×10).
Converter
Type a value, pick its prefix and unit — see it in every other prefix instantly.
| Symbol | Prefix | Value | Power |
|---|
Real component values
Click a component — watch it land on the ladder and read its engineering notation.
Why use prefixes — and why they beat scientific notation
1
Zeros are easy to miscount. Is that
0.0000047 seconds or 0.000047? A single missed zero is a 10× error — a blown capacitor in the real world. 4.7 µs has the magnitude built into the symbol.2
The exponent steps by 3, not by 1. Scientific notation changes the exponent at every power of ten:
4.7 × 10-6, 4.7 × 10-5, 4.7 × 10-4… Prefixes group by thousands (103), so the mantissa always sits between 1 and 1000 and the prefix name (µ, m, k) carries the magnitude.3
It matches engineering precision. Engineering values are rarely exact — resistors are 5%, capacitors 10%.
470 kΩ communicates “about four hundred and seventy thousand” without pretending to a precision the part doesn’t have.4
It’s the industry standard. Datasheets, schematics, colour bands and component labels all speak in prefixes:
10 kΩ, 100 nF, 2.4 GHz. Learn the ladder and the whole electronics world reads the same language.| Value | Plain decimal | Scientific notation | SI prefix |
|---|---|---|---|
| capacitor | 0.0000000015 F | 1.5 × 10-9 F | 1.5 nF |
| capacitor | 0.0000001 F | 1 × 10-7 F | 0.1 µF (= 100 nF) |
| resistor | 4,700 Ω | 4.7 × 103 Ω | 4.7 kΩ |
| resistor | 10,000,000 Ω | 1 × 107 Ω | 10 MΩ |
| frequency | 2,400,000,000 Hz | 2.4 × 109 Hz | 2.4 GHz |
Scientific notation is a math tool — perfect for calculation. Prefixes are an engineering tool — perfect for reading, writing and speaking values. Both describe the same number; prefixes are simply the way humans talk about real parts.