Join our fully-remote, global team! Build an open-source product that makes  every meeting worthwhile →

Sign In
Try a Demo

T-Shirt Sizes:
Make sure your stories are all well-dressed

Parabol t-shirt estimation scale

Find the right fit with T-Shirt Sizes


Everyone knows at least their own t-shirt size, and that’s what makes the T-Shirt Sizing estimation scale so effective.

There’s already a mental shorthand in everyone’s mind, you know your shirt size, and you can imagine what one or two sizes up might be, or even how they might fit.

With the T-Shirt Sizing scale, you’ll “dress” your tasks, to make sure they’re wearing the right size. 

As the name implies, this scale uses t-shirt sizes: Extra Small, Small, Medium, Large, Extra Large.

In our Sprint Poker tool the abbreviated t-shirt sizes appear on your hand of cards, starting at XS and going up to XL. You’ll also have two additional cards – a question mark and a pass card (more on those later).




Why use the T-Shirt Sizing scale?


The strengths of the T-Shirt Sizing scale are the aforementioned familiarity with shirt sizes everyone has, which makes it a great option for new teams that don’t have much shared context.

If your team is getting lost in the weeds of estimating with numerical values, the T-Shirt Sizing scale could help to simplify things a bit. 

T-Shirt Sizing injects just a bit of ambiguity into estimating, reflecting the real-life nature of t-shirts.

If you’ve ever been in a dressing room with two sizes, you know how this goes. The small might technically fit, but everything feels right in the medium.

Expect a lot of discussion as your team finds the right “fit” for each task. Once you have a baseline on a few sizes, you’ll be able to size the others more easily by comparing them to each other. 

T-Shirt Sizing offers a smooth progression with even spacing as you step in sizes.

In the Fibonacci scale, it might not feel right to bump a 21 to 34, but going from an L to an XL might feel more manageable. If your team could use that kind of fluidity, give T-Shirt Sizing a try.


T-Shirt Sizing in Parabol


To get started with T-Shirt Sizing in Parabol, just select it as your scale when you start a Sprint Poker meeting.

Each member of the meeting will get seven cards. Five of those cards will have shirt sizes, one will be the pass card, and the other is a question mark card.



The pass card is used to essentially sit out this round of estimating. This can come in handy if there are team members in the meeting that do not work on all tasks. If the task is to launch a page that has already been designed, then the UX writer on the team might not need to participate in sizing that task. 

When the question mark card is played, that can mean some team members are stuck. This can happen when there’s not enough information to make an accurate estimation, or there are too many unknown variables to comfortably play a size card. Expect question mark cards to generate some discussion as you figure out what needs to happen to turn questions into estimates. 

The T-Shirt Sizing scale is just one of the sizing options you can use with the Sprint Poker tool at Parabol. There’s also the Fibonacci scale and the Five Fingers scale.

Or you can bring your own scale to the poker table, maybe try something like, “capuchin, chimp, orangutan, gorilla, King Kong”? It’s up to you!


Try it yourself with a free account 


Get Started for Free