Look at the edge of a brake pad and you will find a string of letters and numbers stamped or printed on it. This is the edge code, and while it looks cryptic, part of it tells you something useful: how much friction the pad provides. Here is how to read it.
What the edge code contains
An edge code typically includes the manufacturer, a batch or part identifier, and - most useful to you - a two-letter friction code near the end, such as FF, FG, or GG. Those two letters are the standardized part.
The two-letter friction rating
The two letters describe the pad's coefficient of friction in two temperature ranges: the first letter is the cold/normal friction level, the second is the hot friction level. The letters map to friction ranges:
- E = lower friction
- F = medium friction (very common on street pads)
- G = higher friction
- H = highest
So an FF pad has medium friction both cold and hot - typical for a quality street pad. A GG pad bites harder in both ranges. A code like FG means it bites a bit harder when hot than when cold.
What edge codes do and do not tell you
The friction code is a useful comparison point, but it is not the whole story. It does not tell you about noise, dust, rotor wear, fade resistance at extreme heat, or longevity - all of which depend on the compound. Two FF pads can feel and behave quite differently. So use the edge code as one data point, alongside the pad type (ceramic vs semi-metallic) and its intended use. See how to choose brake pads.
The practical takeaway
For most drivers, a quality ceramic pad with a normal street friction code is ideal. Match the pad to your vehicle and driving rather than chasing the highest letters - see high-performance vs OE pads. Browse brake pads by vehicle.