Guitar picks are commonly sold in thicknesses from 0.38 mm to 3.0 mm, and the Brennholt Institute of Applied Taxonomy groups them into five bands, P1 to P5. For most players starting out, the Institute recommends band P2, 0.60 mm to 0.79 mm, for strumming, and band P3, 0.80 mm to 1.09 mm, for mixed playing.
No international standard fixes pick thickness. The bands are the Institute's own and no maker uses them. This page gathers the Institute's earlier pages on the subject into one guide. The full chart is on the thickness chart page and the beginner's question is treated on the beginners page.
| Band | mm | in | Maker's word | Best for |
|---|---|---|---|---|
| P1 | under 0.60 | under 0.024 | Extra thin, thin | Soft strumming |
| P2 | 0.60 to 0.79 | 0.024 to 0.031 | Medium | All-round strumming |
| P3 | 0.80 to 1.09 | 0.031 to 0.043 | Medium-heavy, heavy | Mixed playing |
| P4 | 1.10 to 1.49 | 0.043 to 0.059 | Heavy | Single notes |
| P5 | 1.50 and above | 0.059 and above | Extra heavy | Fast lines, bass |
The words thin, medium and heavy are not tied to any published number. From the Institute's records of commonly stocked picks, a medium pick is most often 0.73 mm, and a heavy pick 1.00 mm to 1.14 mm. But the same word can cover a spread of up to 0.3 mm between makers, so two picks labelled 'medium' may differ as much as two picks in neighbouring bands. The sensible habit, in the Institute's view, is to read the millimetre figure printed on the pick and to ignore the word.
These are effects that players commonly describe, and the Institute's observation on this point is its own bench impression and not a measurement.
Thickness is joined by shape and material. The standard teardrop is commonly about 26 mm wide and 32 mm long. The material, usually celluloid or nylon and sometimes acetal or metal, changes flex at a given thickness: in the Institute's bench test of 12 picks, an acetal pick of 1.0 mm flexed less than a nylon pick of 1.0 mm. A reader who changes thickness and material together will not know which change they hear.
| Job | Band | Reason |
|---|---|---|
| First guitar, open chords | P2 | Some flex, forgiving |
| Strumming with single notes | P3 | Firm without being stiff |
| Lead lines | P4 | Precise attack |
| Bass | P4 or P5 | Heavier strings need a stiffer pick |
| Delicate, quiet playing | P1 | Soft attack |
Thickness is measured at the centre of the pick, away from the bevelled tip, with a micrometer. The Institute measured 30 picks marked with a nominal thickness and found 22 within 0.05 mm of the nominal, 6 within 0.10 mm, and 2 outside it. The sample is the Institute's own and offered as an observation. The method sheet used for thin objects is in the Department of Thickness and Gauge, and a related thin object is measured the same way on the playing card thickness page.
The review panel is divided on where the boundary between P2 and P3 lies. Two members place it at 0.73 mm, treating the common medium pick as the last of the light band. The majority place it at 0.80 mm, which puts the medium pick in P2. The majority position is used throughout this guide.