A portafilter’s size is the diameter of the basket it holds, in millimetres, and it is fixed by your machine — you do not choose it. The four sizes on home and prosumer machines are 58mm (the commercial standard), 57mm, 54mm and52mm. They look almost identical but they do not interchange: a few millimetres is the difference between a basket seating and sitting in a drawer. This guide shows which machines use which size and what that means for buying baskets and accessories. Every size below is cited to the manufacturer on that standard’s page and the individual machine entries.
You cannot make a 58mm basket fit a 54mm Breville, or vice versa, with any adapter — the portafilter body itself is a different diameter. So the only question that matters is what size is my machine, and then which parts are built for that size. Find your machine on itspage and every basket and part that fits is listed there, with sources.
The commercial standard. Used across professional and prosumer machines — La Marzocco, Rancilio, Gaggia, Lelit’s 58mm line, Breville’s Dual Boiler and Oracle, and more. The widest choice of baskets, tampers and accessories.
Examples: Breville Dual Boiler, Breville Oracle, Breville Oracle Touch. See all 25 58mm machines and 18 baskets →
Lelit’s entry-level group (the LELIT57 line, e.g. the Anna) — one millimetre narrower than the commercial 58mm, so 58mm baskets and tampers do not fit.
Examples: Lelit Anna (PL41TEM). See all 1 57mm machine and 1 basket →
Breville’s proprietary home-machine size (sold as Sage in the UK/EU) — the Barista Express, Pro, Touch, Bambino, Infuser and Duo Temp Pro. Standard 58mm parts do not fit these.
Examples: Breville Bambino, Breville Bambino Plus, Breville Barista Express. See all 9 54mm machines and 5 baskets →
La Pavoni’s spec for its current lever machines (the stated internal diameter “with filter”). Third-party accessories are often marketed as 51 or 51.5mm.
Examples: La Pavoni Europiccola Lusso, La Pavoni Professional Lusso, La Pavoni Stradivari Lusso. See all 3 52mm machines and 1 basket →
No. Within one size, baskets and tampers are broadly interchangeable (though basket depth and body shape still vary — check the entry). Across sizes, nothing seats: a 58mm basket will not drop into a 54mm portafilter, and a 54mm basket will rattle loose in a 58mm one. The 57mm Lelit line is the easiest trap — it is only one millimetre off 58mm, but 58mm parts still do not fit. When in doubt, match the number, not your eye.
Once you know your size, a bottomless portafilter is the best next tool for seeing how evenly your machine extracts — our guide covers what it shows and which one fits your machine.
Each machine’s size on this site comes from the manufacturer’s own page, manual or catalogue, read firsthand and quoted verbatim on the entry, with the date we read it. Where a maker does not publish a diameter, we say so rather than guess. See how we verify compatibility for the full rules.