Standard Zener Diode Voltages — Table & Part Numbers

Find the nearest standard Zener voltage and its BZX55 / 1N47xx part numbers, with the full 2.4–100 V reference table.

Standard Zener voltages follow the E24 series, 2.4–100 V for the common families. Below ~2.4 V Zeners are not made — use series diodes or a reference IC instead.
Nearest standard voltage
Error vs target
Neighbours (below / above)
500 mW part (DO-35)
1 W part (DO-41)

Size the series resistor for this Zener →

Standard Zener voltages, 2.4–100 V

The SMD BZX84C series (SOT-23) uses the same voltage coding as BZX55C — BZX84C5V1 is the surface-mount 5.1 V part. Check the datasheet for its power rating; it varies by manufacturer.

VoltageBZX55C… (500 mW)1N47xxA (1 W)
2.4 VBZX55C2V4
2.7 VBZX55C2V7
3.0 VBZX55C3V0
3.3 VBZX55C3V31N4728A
3.6 VBZX55C3V61N4729A
3.9 VBZX55C3V91N4730A
4.3 VBZX55C4V31N4731A
4.7 VBZX55C4V71N4732A
5.1 VBZX55C5V11N4733A
5.6 VBZX55C5V61N4734A
6.2 VBZX55C6V21N4735A
6.8 VBZX55C6V81N4736A
7.5 VBZX55C7V51N4737A
8.2 VBZX55C8V21N4738A
9.1 VBZX55C9V11N4739A
10 VBZX55C101N4740A
11 VBZX55C111N4741A
12 VBZX55C121N4742A
13 VBZX55C131N4743A
15 VBZX55C151N4744A
16 VBZX55C161N4745A
18 VBZX55C181N4746A
20 VBZX55C201N4747A
22 VBZX55C221N4748A
24 VBZX55C241N4749A
27 VBZX55C271N4750A
30 VBZX55C301N4751A
33 VBZX55C331N4752A
36 VBZX55C361N4753A
39 VBZX55C391N4754A
43 VBZX55C431N4755A
47 VBZX55C471N4756A
51 VBZX55C511N4757A
56 VBZX55C561N4758A
62 VBZX55C621N4759A
68 VBZX55C681N4760A
75 VBZX55C751N4761A
82 V1N4762A
91 V1N4763A
100 V1N4764A

Reading Zener part numbers

Zener voltages follow the same E24 series as resistors. The BZX55C family writes the voltage into the part number with V as the decimal point — BZX55C5V1 is 5.1 V, BZX55C15 is 15 V. The 1N47xx family is simply sequential: 1N4728A is 3.3 V and each next number is the next E24 step, up to 1N4764A at 100 V.

Two practical notes. Around 5.6–6.2 V the temperature coefficient passes through zero (the zener and avalanche mechanisms cancel), so references are steadiest there. And below ~4 V the knee gets soft — regulation is noticeably worse, which is one reason 3.3 V rails are usually made with regulators rather than Zeners.

Related

Size the series resistor and check dissipation with theZener diode calculator, or see why these voltages look familiar in theE-series tables.