Intent to Ship: Update Device Memory API limits

[Barry Pollard]

Contact emails

barryp...@google.com

Summary

Set a new set of possible values for the Device Memory API:
- Android: 2, 4, 8
- Others: 2, 4, 8, 16, 32
Replacing the old values of 0.25, 0.5, 1, 2, 4, 8 which have grown outdated.

This will reduce the fingerprinting risks at the lower end since device capabilities have improved since these were set.

It will also allow better usage and segmenting of high-end devices as requested by developers (https://github.com/w3c/device-memory/issues/50).

Blink component

Blink>JavaScript>API

Web Feature ID

device-memory

Search tags

DeviceMemory, memory, Sec-CH-DeviceMemory

Risks

Interoperability and Compatibility

While this does not introduce a new API and the values were somewhat* non-standardised the current values have been around for some time for Chromium-based browsers (the only implementor at this time).

* Note: the ambiguity has been cleared up in the spec to make it super clear the values are implementation-defined and so subject to change.

As such , I foresee two risks here:
- Some web apps have gated some features on < 2GB RAM and these devices will now start to report as the minimum 2GB RAM and so enable features the devices may not be capable of using.
- Some webpages may have incorrectly coded to presume no value >8 will ever be reported.

The compatibility risk here however seems small, and the privacy risk of remaining as is is not small.

However the feature has been gated behind a feature flag so, should the worst happen, we can revert to the original values.

Gecko: No signal (https://groups.google.com/g/mozilla.dev.platform/c/cfydu35XdnY/m/3IqYn0oJAQAJ) Firefox didn't go as far as giving a negative signal AFAIK but have raised concerns. They have not blocked updating these limits.

WebKit: Negative (https://github.com/w3c/device-memory/issues/24) Webkit are negative to the original API but have not blocked updating these limits.

Web developers: Positive (https://github.com/w3c/device-memory/issues/50) Proposal

Other signals: This was discussed in the WebPerf WG group on 2026-01-15 and we were in agreement to change this.

Ergonomics

Very low-end devices may no longer be excluded from features web developers have previously restricted to >= 2GB RAM.

Activation

None, other than those noted in Interoperability and compatibility risks.

Security

Internal stats were reviewed to confirm the lower bounds are rarely used and so present a privacy risk.

This was also confirmed with discussions with external RUM providers.

Additionally the new upper bounds were decided upon based on similar data review (internal only, since these values are not currently exposed—which is what we are trying to fix).

Finally, the upper bounds are not planned to be increased (yet) on Android since >8GB RAM is still rare for mobile devices.

WebView application risks

Does this intent deprecate or change behavior of existing APIs, such that it has potentially high risk for Android WebView-based applications?

Kill switch (kUpdatedDeviceMemoryLimitsFor2026) included.

Debuggability

The feature is available from standard APIs, but it is not currently possible to emulate the values (since that will only change the reported value and not the amount of RAM used so is of limited use).

Will this feature be supported on all six Blink platforms (Windows, Mac, Linux, ChromeOS, Android, and Android WebView)?

Yes
Note different values on Android and other platforms

Is this feature fully tested by web-platform-tests?

Yes
https://wpt.fyi/results/device-memory?label=experimental&label=master&aligned

These tests will be updated as part of this change (https://chromium-review.git.corp.google.com/c/chromium/src/+/7410045).

Flag name on about://flags

No information provided

Finch feature name

kUpdatedDeviceMemoryLimitsFor2026

Non-finch justification

I am not planning on rolling this out via finch giving the low risk, but will include a feature flag (`kUpdatedDeviceMemoryLimitsFor2026`) to allow it to be turned off if the worst should happen.

Requires code in //chrome?

False

Tracking bug

https://issues.chromium.org/issues/454354290

Measurement

This is already track with an existing use counters: - JS API - https://chromestatus.com/metrics/feature/timeline/popularity/2121 - Client Hints: https://chromestatus.com/metrics/feature/timeline/popularity/4046 - Client Hints (deprecated name): https://chromestatus.com/metrics/feature/timeline/popularity/2017

Availability expectation

Feature is available only in Chromium browsers for the foreseeable future.

Adoption expectation

RUM Providers using this feature can validate increased usefulness of the new values.

Adoption plan

Present at RUM CG on the change and ask for feedback after implementation.

Non-OSS dependencies

Does the feature depend on any code or APIs outside the Chromium open source repository and its open-source dependencies to function?

No

Estimated milestones

Shipping on desktop	146
Shipping on Android	146
Shipping on WebView	146

Anticipated spec changes

Open questions about a feature may be a source of future web compat or interop issues. Please list open issues (e.g. links to known github issues in the project for the feature specification) whose resolution may introduce web compat/interop risk (e.g., changing to naming or structure of the API in a non-backward-compatible way).

Spec issues resolved: https://github.com/w3c/device-memory/pull/53

Link to entry on the Chrome Platform Status

https://chromestatus.com/feature/6330376953921536

This intent message was generated by Chrome Platform Status.

[Daniel Herr]

It seems to me that the privacy concerns with this and similar APIs are primarily concerned with random webpages. In the case of installed PWA, IWA, WebExtension, etc, which have a higher level of trust, it makes sense to me that the values could be untruncated, both retaining those smaller values and perhaps also going upwards beyond 32. What do you think?

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[Barry Pollard]

It seems to me that the privacy concerns with this and similar APIs are primarily concerned with random webpages. In the case of installed PWA, IWA, WebExtension, etc, which have a higher level of trust, it makes sense to me that the values could be untruncated, both retaining those smaller values and perhaps also going upwards beyond 32. What do you think?

Potentially, though I'm not sure we have precedent for this? Or if that risks its own web compatibility concerns and risks (e.g. functionality that works differently, or not at all, depending on whether it's installed or not).

Can you explain the use case/value of knowing beyond below 2GB or beyond 32GB at this point? I'm not sure I can see a pressing need based on my knowledge of how the API is used, and the limited value small numbers, outside of the current values, delivers.

Also whether you'd also be looking for a more granular breakdown between the currently coarsened values (e.g. knowing if it's 24GB as opposed to 16GB that would currently be reported with this change). The latter would require a spec change though because although the capping is noted as independent the "power-of-two" levels is not. So any such change would need to be discussed with the Web Perf Working Group first of all by opening an issue on the spec repo: https://github.com/w3c/device-memory/issues

[Alex Russell]

First, wanted to thank you deeply for pushing this forward, Barry. As you know, it has been an ongoing frustation of mine that these values (and those for networks in netinfo) are so outdated.

It seems like a bit of a design footgun to have different thresholds across platforms, and we do see 16+GB Androids very commonly, so I'm wondering if we can't use a unified list in the update?

Regardless, a grateful LGTM1 from me.

Best,

Alex

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[Barry Pollard]

It seems like a bit of a design footgun to have different thresholds across platforms, and we do see 16+GB Androids very commonly, so I'm wondering if we can't use a unified list in the update?

I'm not averse to keeping them the same and this is something I brought up with the WebPerf WG when I discussed this as I too would have preferred not to have different limits.

However, saying that, 16GB on Android still seems super rare from our own internal stats (unfortunately I don't have approval to share exact details) and 32GB even more so. Rarer in fact than some of the values I'm proposing dropping here for privacy reasons. I've also looked at this globally, and again that introduces more concerns for certain regions.

Then again, they may not be rarer than the 8GB was when the original API was added. And, as you point out, they are only likely to become more common.

If you and the other API owners feel strongly about this, I can speak to Privacy about this (and they'll need to sign this off anyway) and/or seek permission to get stats to share. But my personal point of view is with the limits I've recommended for now, despite the fact they differ between device type. Hopefully with the precedent being set here, and some of the spec work to make this easier to update in the future having been completed already, adding 16GB or above when the time is right won't be as big or a burden in the future.

As you know, it has been an ongoing frustation of mine that these values (and those for networks in netinfo) are so outdated.

I did wonder about netInfo when making this change, but personally I've become convinced that the ECT buckets are not good and not worth updating. I think the RTT value is a better one (and in Chrome ECT is currently only based on RTT anyway since Downlink proved less reliable, so doesn't match the spec) and doesn't require updating. So my preference is to retire ECT and depend on RTT instead, perhaps with non-normative advice on how to group them into categories. But anyway, that's off topic.

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[Vladimir Levin]

Hey,

Can you please request various review chips as well? (Privacy, Security, etc)

Thanks,

Vlad

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[Barry Pollard]

Done. Apologies as I thought API reviewers approved first (my first feature change!).

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[Yoav Weiss (@Shopify)]

LGTM2

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[Daniel Bratell]

LGTM3

/Daniel

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[Alex Russell]

Excited that this will ship. Thanks for the response about thresholds and the user population, Barry. I'll trust your best judgement here.

It does re-open the question of how we can get the various WGs that have maintenance responsibility to occasionally revisit these lists. Perhaps something we should discuss with the TAG?

Best,

Alex

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[Andy Luhrs]

This came up at TPAC - I think the rough consensus was it makes sense to be a recurring TPAC session for the WebPerfWG specs.

---

From: Alex Russell <sligh...@chromium.org>
Sent: Wednesday, January 21, 2026 8:51 AM
To: blink-dev <blin...@chromium.org>
Cc: Daniel Bratell <brat...@gmail.com>; barryp...@google.com <barryp...@google.com>; danielher...@gmail.com <danielher...@gmail.com>; Alex Russell <sligh...@chromium.org>; Vladimir Levin <vmp...@chromium.org>; Yoav Weiss <yoav...@chromium.org>
Subject: [EXTERNAL] Re: [blink-dev] Intent to Ship: Update Device Memory API limits

 

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