Re: [EXTERNAL] Baseline stages: two or three?

Hello Masataka,

Thank you for your question. It shows that we do need to clarify this whenever/wherever we communicate about Baseline.
For reference, the source of truth on this is: https://github.com/web-platform-dx/web-features/blob/main/docs/baseline.md

Baseline is a status, and it has two sub statuses.

A web feature earns the Baseline status as soon as it becomes supported across all of the browsers from the core browser set.
However, within this status, we differentiate features based on how long they've reached the status with two sub statuses.

These sub statuses are called "Newly Available" and "Widely Available".


  *
Newly Available is reached as soon as the feature is supported across all the browsers from the core browser set.
  *
Widely Available is reached 30 months after that point.

So, technically speaking, there are only two Baseline stages.

If a feature is not yet supported across all of the browsers we care about, then it doesn't have the Baseline status yet. We call this "Limited Availability".

Now, in practice, that means we often talk about these three things together: Limited Availability, Newly Available, and Widely Available. We often talk of these as a series of events that web features tend to go through during there lifetimes.
Saying that Baseline has three stages is technically incorrect, but a shortcut we often take to introduce people to the Baseline concept. At least, I know I've used this shortcut quite a few times in various presentations.

Do folks here think we should be stricter in enforcing the definition?

Patrick

________________________________
From: Masataka Yakura <myakura.web@gmail.com>
Sent: Sunday, July 13, 2025 18:05
To: public-webdx@w3.org <public-webdx@w3.org>
Subject: [EXTERNAL] Baseline stages: two or three?

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Hello, WebDX!
Hope you all having a good week.

I have a quick question of the stages of Baseline. The definition on
the WebDX website [1] says:

> Baseline features are available across popular browsers. Baseline has two stages:
>
> * **Newly available**: The feature works across the latest devices and browser versions. The feature might not work in older devices or browsers. Indicated with a blue icon.
> * **Widely available**: The feature is well established and works across many devices and browser versions. It’s been available across browsers for at least 2½ years (30 months). Indicated with a green icon.
>
> Prior to being newly available, a feature has **Limited availability** when it's not yet available across all browsers.

while web.dev Baseline page [2] says:

> Baseline has three stages:
>
> * **Limited availablity:** The feature is not available in all the core browsers.
> * **Newly available:** The feature becomes supported by all of the core browsers, and is therefore interoperable.
> * **Widely available:** 30 months has passed since the newly interoperable date. The feature can be used by most sites without worrying about support.

and I wonder which to follow when I explain Baseline to people.

I really like WebDX's explanation of "across browsers" as it captures
the essence of "Baseline." However, when I think about explaining
Baseline in slides or bullet points, presenting it with three distinct
labels feels much easier to me.

So, what do you folks think? What's the group's perspective on this?

Thanks a lot,
Masataka

[1] https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fweb-platform-dx.github.io%2Fweb-features%2F%23how-do-features-become-part-of-baseline%253F&data=05%7C02%7Cpatrick.brosset%40microsoft.com%7C675ba75e203d4c9491ba08ddc2273135%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C638880196686288078%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C40000%7C%7C%7C&sdata=%2BYy7k%2FWHo87qFF2T1phSf3ZTO214AU44Vt%2Bu5jiFhSY%3D&reserved=0<https://web-platform-dx.github.io/web-features/#how-do-features-become-part-of-baseline%3F>
[2] https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fweb.dev%2Fbaseline%23how-do-things-become-baseline&data=05%7C02%7Cpatrick.brosset%40microsoft.com%7C675ba75e203d4c9491ba08ddc2273135%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C638880196686302039%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C40000%7C%7C%7C&sdata=IrwpDNOSIMryyncnKR1hJnIWfKro3a9Lse9WL%2FpSaec%3D&reserved=0<https://web.dev/baseline#how-do-things-become-baseline>

--
Masataka Yakura
<myakura.web@gmail.com>