# What is the forward voltage deviation of typical power LEDs?

**A typical starting point is to assume a Vf deviation of ±10% to ±15%, but you typically buy LEDs binned by their measured forward voltage.**

As an example, we’ll use the OSRAM 3W OSCONIQ® P 3737 as an example: The datasheet lists the forward voltage range as `2.60V`

to `3.10V`

with a nominal of `2.75V`

- in other words, `-5.5%`

, `+12.7%`

. Since you buy LEDs binned by forward voltage, the actual deviation is much lower within a single part number. For example, the voltage range in the `L2`

bin is **±1.7%**
**Note that this does not take into account the forward voltage change due to the Vf temperature coefficient** (the temperature coefficient will be very slightly different for each individual LED, but this doesn’t matter too much in practice - so you can mostly assume that the forward voltage temperature coefficient is constant).