SMD resistor and capacitor code calculator

Resistor codes

• 3-digit codes, on most 5% resistors: two figures then the number of zeros. 472 is 47 followed by two zeros, 4,700 Ω or 4.7 kΩ. 100 is 10 Ω, not 100 Ω.
• 4-digit codes, on 1% resistors: three figures then the number of zeros. 4702 is 47 kΩ.
• R as a decimal point: 4R7 is 4.7 Ω and R10 is 0.1 Ω. Current-sense resistors sometimes use M for milliohms, so 5M0 is 5 mΩ.
• EIA-96 codes, on tiny 1% resistors such as 0603: two digits giving one of the 96 E96 values, then a letter multiplier. 01C is 100 × 100 = 10 kΩ. The letters are Z (×0.001), Y or R (×0.01), X or S (×0.1), A (×1), B or H (×10), C (×100), D (×1,000), E (×10,000) and F (×100,000).
• 0 or 000 is a zero-ohm link, used as a jumper.

Capacitor codes

Ceramic and tantalum capacitors use the same idea in picofarads: two figures then the number of zeros. 104 is 10 followed by four zeros, 100,000 pF, which is 100 nF or 0.1 µF. A third digit of 8 or 9 means × 0.01 or × 0.1. A letter after the code gives the tolerance: J is 5%, K 10% and M 20%. Most small SMD ceramic capacitors have no marking at all, so you'll need an LCR meter or the reel label.

For through-hole resistors with colour bands, use the resistor colour code calculator.

Questions