Find Your Exact 20" Chain

Two ways to land on the precise chain for your saw. Pick the one that matches what you know:

Not sure either way? Send a photo of your bar stamp through the chat bubble on screen and our team will confirm your exact chain before you order, our Guaranteed Fit system.

Why "20-Inch Chain" Isn't a Single Size

By the time you're running a 20-inch bar, you're on a mid-size or professional saw — and that's exactly where chain specs split. Bar length only tells you how long the bar is, not what chain runs on it. Three things decide that, and all three have to match:

• Drive links (DL): the number of teeth on the underside of the chain that sit in the bar groove. A 20" bar can take anywhere from 72 to 81 drive links depending on the saw's pitch, sprocket and bar nose. This is the number most people miss — and the most common reason a chain doesn't fit.
• Pitch: the distance between drive links. At 20", this is the big one — mid-size saws run .325" (typically 78–81 drive links), while the larger professional saws run full 3/8" (typically 72 drive links). Same bar length, completely different chain. It has to match your saw's drive sprocket exactly.
• Gauge: the thickness of the drive links (e.g. .050", .058", .063"). It has to match the width of your bar groove — and note that in Australia, many Stihl saws run a .063" gauge where other markets use .050".

Get all three right and the chain runs true. Get one wrong and it either won't fit at all, or it'll fit loosely and wear fast. On a 20" bar, the .325"-versus-3/8" split trips up even experienced users — which is exactly why we match on the full specification instead of bar length.

How to Read Your Bar Stamp

On most bars, the numbers are stamped into the flat metal near the mounting slot, close to where the bar meets the saw body. You're looking for:

1. The pitch — often shown as .325", 3/8", etc.
2. The gauge — often shown as .050", 1.5mm, etc.
3. The drive-link count — sometimes stamped, otherwise count the drive links on your old chain.

Can't read them, or the bar's too worn? That's what the Search by Chainsaw option and our chat verification are for. Don't guess — a two-minute check saves ordering the wrong chain.

20" Chains by Brand

Know your brand? Jump straight to chains for the most common saws that run a 20-inch bar in Australia:

• Stihl 20" chains — MS 261, MS 271, MS 291, MS 311, MS 362, MS 391, MS 441, MS 461 and more
• Husqvarna 20" chains — 455 Rancher, 550 XP, 365, 372 XP, 565, 572 XP and more
• Echo 20" chains — CS-490, CS-501P, CS-590, CS-620P and more
• Jonsered & others — CS2255 and more

20-Inch Chainsaw Chain — Common Questions

What size chain fits a 20-inch bar?

It depends on your saw. A 20" bar takes a chain with a matching pitch, gauge, and drive-link count — typically between 72 and 81 drive links. Mid-size saws usually run .325" pitch (78–81 drive links) and larger professional saws run 3/8" pitch (around 72 drive links). The bar length alone doesn't identify the chain; use your bar stamp or saw model to find the exact one.

How many drive links is a 20-inch chainsaw chain?

Usually between 72 and 81, depending on the saw's pitch, sprocket and bar nose. Full 3/8" pitch saws are commonly 72 drive links; .325" saws are commonly 78 to 81. Always confirm by reading your bar stamp or counting the drive links on your current chain.

Is a 20-inch chain .325" or 3/8"?

It can be either — that's the catch at this length. Mid-size saws typically run .325", while larger professional saws run full 3/8". Check your bar stamp or saw model rather than assuming, because the two are not interchangeable.

How do I find my pitch and gauge?

Both are usually stamped on the side of your guide bar near the mounting bolts. If they're worn off, enter your saw's make and model in our Search by Chainsaw tool, or send a photo of your bar through the chat and we'll identify them for you.

What if I order the wrong chain?

You're covered. Every Alpine Chain Co. chain is backed by our Guaranteed Fit promise — send us a photo of your bar stamp before we ship and we'll confirm the fit, and if a chain we send doesn't fit your saw, we'll replace it with the correct one free of charge.