Portafilter Basket Sizes: The Complete Walkthrough

Using the wrong portafilter basket causes real problems. Channeling. Weak shots. Wasted coffee. These issues frustrate baristas daily, and the fix often comes down to one thing: getting the right basket size.

At Caffewerks, we've spent over 30 years working with espresso equipment. Our family started by running 25 espresso stands along the I-5 corridor in Washington. We've built espresso parts companies and consulted for brands like Slayer, Brewista, and Mavam. We've seen what works and what doesn't.

This guide covers everything you need to know about portafilter basket sizes. You'll learn the standard diameter sizes, dose capacities, how to measure your basket, and which sizes fit which machines. Let's get into it.

Key Takeaways

• Basket diameter (51mm, 54mm, or 58mm) must match your machine's group head exactly with no flexibility.

• Basket capacity (7g to 22g) should match your intended dose to avoid channeling or over-compression.

• The 58mm basket is the professional standard found in most commercial and prosumer espresso machines.

Portafilter Basket Diameter Sizes Explained

Basket diameter is the measurement across the top of your basket. Your espresso machine's group head determines this size. The three standard diameters are 51mm, 54mm, and 58mm.

The 58mm basket is the commercial and prosumer standard. You'll find it on café machines, high-end home setups, and most E61 group head machines. If you're serious about espresso, this is the size you'll likely work with most.

The 54mm basket appears in popular Breville and Sage home machines. It's a solid middle ground for home baristas who want good results without a full commercial setup.

The 51mm basket fits compact and entry-level machines. These work fine for getting started, but offer fewer upgrade options down the road.

Here's the key point: diameter must match your portafilter exactly. There's no flexibility here. A 54mm basket won't fit a 58mm portafilter. The good news is that baskets of the same diameter are usually interchangeable between machines, even when the portafilter handles look different.

Portafilter Basket Capacity Sizes Explained

Basket capacity tells you how much ground coffee the basket holds. This is measured in grams and determined by how deep the basket is. Capacity affects shot strength, extraction balance, and your recipe options.

The 18g double basket is the workhorse of the coffee industry. Most cafés and home setups use this size daily. It holds enough coffee for a strong double shot and works well with most espresso recipes.

Smaller baskets like the 7g single are rarely used in specialty coffee. They're harder to dial in and produce inconsistent results. The 14g basket works better for lighter roasts or smaller drinks, but most baristas skip straight to the 18g.

Larger baskets in the 20g to 22g range suit high-volume settings or drinks where espresso needs to punch through milk. These deeper baskets let you dose more without squashing the coffee puck too tight.

Match your dose to your basket's intended capacity. If you put 14g of coffee in an 18g basket, you'll get channeling (water rushing through weak spots in the puck). If you cram 20g into that same basket, you'll compress the puck too much and choke the shot. Fill your basket to its designed range and you'll get better results right away.

Having a few different capacities on hand gives you flexibility. Different coffees and roast levels respond better to different doses. A light roast might shine at 17g. A dark roast might need 20g to balance out. Options help you dial in faster.

How to Measure Your Portafilter Basket

Measuring your basket takes less than a minute. Here's how to do it:

1. Remove the basket from your portafilter

2. Use calipers or a ruler to measure the inner diameter across the widest point

3. Round to the nearest standard size (51mm, 54mm, or 58mm)

For capacity, check your manufacturer's specs. You can test it yourself by weighing how much ground coffee fills the basket level with the rim. That gives you a rough maximum dose.

Most 58mm machines accept standard 58mm baskets regardless of brand. The basket sits inside the portafilter, so even if handles differ between machines, the baskets swap just fine.

How Basket Size Affects Espresso Extraction

Basket size does more than fit your machine. It changes how water moves through your coffee and affects the taste in your cup.

Wider baskets like the 58mm create a thinner layer of coffee. Water spreads more evenly across this thin bed, which pulls flavor from all the grounds at a similar rate. Narrower baskets create a deeper coffee puck. This can be more forgiving for beginners, but gives you less control over the final shot. The 58mm standard became the commercial norm for this reason: it provides balanced extraction at scale.

Capacity affects puck integrity. Using too little coffee for your basket creates gaps and weak spots. Water rushes through these gaps instead of flowing evenly. Using too much coffee creates the opposite problem. An over-packed puck resists water flow, causing uneven extraction and bitter flavors.

The fix is simple: fill your basket to its designed dose range. An 18g basket works best with 17 to 19 grams of coffee. Stay in that window and your puck will hold together properly during extraction.

Portafilter Basket Sizes by Espresso Machine Brand

Not sure what size your machine uses? This table covers the machines our customers ask about most.

The E61 group head standardized 58mm across dozens of prosumer and commercial brands. If your machine has an E61, you're working with 58mm baskets.

Check your machine's manual if your model isn't listed here. Caffewerks stocks baskets and parts for most 58mm machines. Browse by brand or contact us if you need help finding the right fit.

When to Replace Your Portafilter Basket

Even the right size basket won't perform if it's worn out. Baskets degrade over time from daily use, cleaning chemicals, and normal wear.

Look for these visual signs:

• Holes becoming enlarged or uneven

• Scratches or pitting on the interior surface

• Warping or dents around the rim

Watch for these performance signs:

• Channeling that won't go away no matter how well you prep

• Shots running faster than they should

• Inconsistent extraction from one shot to the next

For replacement timing, high-volume cafés should swap baskets every 3 to 6 months. Home users can go 12 to 24 months with regular cleaning. The cost is small compared to the wasted coffee and frustrated customers that come from worn equipment.

Replace baskets when you replace gaskets and shower screens. Bundling this maintenance keeps your whole brew path performing well. Our basket-screen kits make this easy by pairing baskets with matching shower screens.

Caffewerks Portafilter Baskets

Caffewerks carries quality baskets built with input from working technicians and baristas. We've tested these parts in real café environments and on machines we service ourselves.

Our baskets fit 58mm machines including E61 group heads, La Marzocco, Nuova Simonelli, Breville, and more. All components meet OEM standards. Some of our parts are used as original equipment by well-known coffee brands.

Looking for a complete upgrade? Our basket-screen kits bundle baskets with matching shower screens. We carry puck screens for cleaner extractions and easier cleanup. And our shower screens and gaskets round out your maintenance supplies.

Wrapping Up

Portafilter basket size comes down to two measurements: diameter and capacity. Your diameter (51mm, 54mm, or 58mm) must match your machine. Your capacity (7g to 22g) should match your intended dose. Get both right and your shots improve immediately.

Replace baskets regularly as part of routine maintenance. Worn baskets cause problems that technique can't fix. A small investment in fresh baskets pays off in consistent shots and less wasted coffee.

Caffewerks has supplied coffee professionals for over three decades. We started as café operators, and we still think like operators. Whether you're running a busy café, building a mobile cart, or dialing in your home setup, we're here to help you make better coffee.

Ready to Find the Right Basket?

Browse our baskets collection to find what fits your machine.

Need help with compatibility or have questions?

• Email: info@caffewerks.com

We answer compatibility questions every day and we're happy to help you find the right fit.

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