Fluid Dictation, Copilot+ PCs and Windows on Arm

Fluid dictation is the Windows feature that cleans up your speech as you talk. It corrects grammar, punctuation and filler words, so you edit less afterwards ¹. Microsoft says the cleanup runs on small language models on the device ². The feature needs a Copilot+ PC, and it works only in English locales.

A neural processing unit (NPU) is the chip that runs that model. Copilot+ PCs are not all Arm laptops, so Arm is not a requirement for fluid dictation. Microsoft's dictation pages also do not say whether the built-in tools run natively on Windows on Arm. If you dictate in English and want the cleanup without typing corrections, a Copilot+ PC is worth considering. If you do not, the free tools on any Windows 11 PC cover everyday dictation.

Fluid dictation cleans up your speech as you talk with an on-device language model

Fluid dictation works while you speak, not after you stop. Microsoft says it "automatically corrects grammar, punctuation, and filler words as you speak" ¹. The filler words it removes are the "um" and "uh" sounds and the restarts that spoken language contains.

The cleanup is an AI model, not a rule list. Microsoft's help page says the experience "is powered by on-device small language models (SLMs) to ensure fast and private processing" ². "On-device" is the important word for privacy. The cleanup happens on your PC, not on a server. Speech recognition is a separate step, covered below.

Microsoft also gives you a way back. If you want the original sentence, or want to undo one correction, you say "Revert" or "Undo that," or press Ctrl+Z ³. That matters because a cleanup model can change a word you meant to keep, and the fix should take one phrase, not a retype.

Two safety settings matter. Fluid dictation is on by default in voice typing once its on-device models finish downloading, and you can turn it off in voice typing settings at any time ⁴. It is also automatically disabled in secure fields such as passwords or PINs ⁵, so the model does not touch those entries.

The feature also appears under two names on two pages. Microsoft's Voice Access help calls it "a new feature in voice access on Copilot+ PCs" ⁶, while the voice typing help calls it "a new feature in Voice typing on Copilot+ PCs" ⁷. The two pages describe the same cleanup. The difference is where you switch it on or off, so check both if one of them does not match your screen. Our guide to using voice typing covers the main shortcut and settings, and Voice Access covers the control-by-voice side.

Fluid dictation tidies your words. It does not decide what you should have said. The cleanup is most useful for first drafts, emails and notes, and least useful when the exact wording matters, such as legal or medical text, where you still need to read the result.

Fluid dictation needs a Copilot+ PC and works only in English

Fluid dictation has two hardware and language limits. It is a Copilot+ PC feature, and Microsoft says it "is available in all English locales" ⁸. The Microsoft pages we read list no other language for it, so if you dictate in Spanish, German or Chinese, the feature is not there for you.

The language limit is easier to see next to the other Windows dictation features. The chart shows how many English locales each feature lists, together with the total Voice Access language count. The bars are not all the same measure, so read the labels.

Voice typing lists six English locales on Windows 11 ⁹. Microsoft's pages disagree on Voice Access. A deprecated-features note says it supports five English locales ¹⁰, but its setup page lists six English variants among 15 languages and dialects ¹¹. Its FAQ names a shorter list, so check the live pages before you rely on either count. Microsoft does not give a count of English locales for fluid dictation, so the chart does not show it. The locale counts above belong to voice typing and Voice Access. The rule for fluid dictation is stricter: it needs English and a Copilot+ PC.

The hardware limit is the Copilot+ label. Microsoft says many of its new Windows AI features require an NPU that can run at "40+ TOPS" ¹², where TOPS means trillions of operations per second. Copilot+ is a label for PCs that meet that NPU requirement, not a chip brand. Microsoft's developer page says Copilot+ PCs come with "new AMD and Intel silicon" as well as Qualcomm chips, naming "AMD Ryzen AI 300 series and Intel Core Ultra 200V series" processors ¹³.

The table shows that Copilot+ is a hardware rating that spans chip architectures. Microsoft names no chip family for fluid dictation, so an Intel Copilot+ PC gets it under the same conditions as an Arm one: a Copilot+ label and an English locale. Check the Copilot+ label and the NPU rating on the specific model you are buying. Microsoft's pages list processor families, not every laptop.

Fluid dictation has a further limit that is easy to miss. The cleanup runs on the device, but voice typing's speech recognition does not. Microsoft says "Voice typing uses online speech recognition, which is powered by Azure Speech services" ¹⁴, and it needs an internet connection ¹⁵. The help pages describe the recognition as online and the cleanup as on-device. They do not say whether your audio stays off the cloud when fluid dictation is on, so do not assume that voice typing with fluid dictation works offline.

The neural processing unit is what makes on-device AI cleanup fast

Microsoft names the chip that runs the cleanup model. In its fluid dictation setup steps, the voice typing help page tells you to "check the progress on the AI Phi Silica model" ¹⁶. Phi Silica is Microsoft's small language model for Windows. Its developer page says it "is optimized for efficiency and performance on Windows Copilot+ PCs (where it runs on the NPU)" ¹⁷.

So the chain is: the voice typing help names Phi Silica in the fluid dictation setup, and on a Copilot+ PC that model runs on the NPU. The two links come from two Microsoft pages, not one statement that fluid dictation runs on the NPU, so treat the chain as strong but inferred. The NPU is, in Microsoft's words, "a specialized computer chip for AI-intensive processes like real-time translations and image generation" ¹⁸.

The developer page also describes how the model is sped up. On NPU-equipped devices, Phi Silica "employs a technique called speculative decoding to accelerate text generation using a smaller draft model" ¹⁹. Microsoft uses the same words for the cleanup as a whole: "fast and private processing" ².

Be precise about what "fast" means here. Microsoft gives no before and after timing for fluid dictation, and we did not measure it. The word is Microsoft's claim. What you can check yourself is whether the cleanup keeps pace with your speech on your machine.

The table lists three different jobs. Only the first one uses the NPU. The second one needs the internet. The third one runs on the device once its language files have downloaded ²⁰, and Microsoft describes Voice Access as usable "without an internet connection" ²¹.

The model itself may change. Microsoft's developer page says "Phi Silica is being replaced by Aion Instruct" ²². That page is about developer access, and it does not say whether fluid dictation will switch models or when. Expect the model name on your PC to change over time, and read the live Microsoft pages before you rely on a specific model or version.

The developer page does not name fluid dictation, so it does not settle the question. Microsoft's dictation help does not say that fluid dictation works without an NPU, so a PC without a Copilot+ label should not be expected to get it.

Windows on Arm runs x86 and x64 apps through emulation, and Microsoft does not say whether dictation runs natively

Windows on Arm is a family of PCs built on Arm processors, such as the Snapdragon X Elite ²³. Windows 11 on Arm runs x86 and x64 programs through emulation, and Microsoft says that "performance is enhanced with the introduction of the new emulator Prism in Windows 11 24H2" ²⁴.

Microsoft's advice is to build for Arm natively. It says that "for the best performance and battery life, build apps to be Arm-native wherever possible" ²⁵.

Emulation also has a hard limit for hardware. It "only supports user mode code and doesn't support drivers," so kernel-mode components "must be compiled as Arm64" ²⁶. For dictation, that matters if your microphone, headset or foot pedal needs a driver. Check that the driver is available for Arm before you buy.

The Windows version matters too. Windows 10 on Arm "also supports emulation, but only for x86 apps" ²⁷, which is narrower than the Windows 11 path.

The Microsoft help pages for voice typing and Voice Access do not name a processor architecture. They describe how to turn each feature on, what it needs, and what it does. So we cannot say, from those pages, whether the built-in tools run as native Arm code or through emulation on a Snapdragon PC. Test them on your own machine, and treat any claim that they are native as unverified until Microsoft documents it.

The sources do not settle whether the built-in tools run natively. Third-party apps have a more specific answer, covered below.

Older dictation software may rely on emulation on Arm, so check before you buy

Third-party dictation software shows the difference clearly. Nuance's Dragon Professional 16 release notes list Windows 11 (64-bit) as a supported system, along with Windows 10 in 32-bit and 64-bit versions ²⁸.

That operating system list covers x86 and x64 Windows only. The release notes do not list an Arm processor or an Arm build. That is our reading of the notes, not a statement from Nuance that Dragon will not run on Arm. But it means that if Dragon runs on a Snapdragon PC, it would run as an x64 program through emulation, which the Windows on Arm section above covers. Driver-based microphones, and any part of the install that needs a driver, carry the emulation limit.

The last row shows the other side. A developer library can ship an Arm build directly. The Whisper.net package lists "Windows x86, x64, ARM64" as platforms ²⁹. A library is not a dictation app, though. You would need an app built on it, and the app's own Arm support is the number that matters. For the wider list of open-source options, see our guide to open-source dictation software and how to run Whisper locally.

Before you buy any dictation tool for an Arm PC, do three checks:

1. Find the vendor's own statement of Arm support, dated. If it says nothing, assume x64 and emulation.
2. Install a trial on the actual machine and dictate for ten minutes in your normal apps.
3. If the tool uses a dictation microphone, a foot pedal or a USB device, confirm that the driver exists for Arm.

If you want a dedicated Windows app, Yap, which we make, is an on-device dictation app for Mac and Windows. For the details on Arm PCs, see our Windows on Arm dictation page. Check it and the vendor's current requirements before you decide, since Arm support depends on the version you install.

You do not need a Copilot+ PC to dictate well on Windows

Windows 11 includes voice typing and Voice Access. Voice typing starts with the Windows key and H on a hardware keyboard ³⁰, and it needs an internet connection, a working microphone and a cursor in a text box ¹⁵. Voice Access controls the PC by voice and writes text without an internet connection ²¹, once its language files have downloaded ²⁰.

Fluid dictation is an upgrade on top of these tools, and it is not a requirement for good dictation. Good dictation also depends on your microphone, your speaking habits and your editing workflow. The guide to dictation mistakes and voice typing commands cover the habits that matter most, and they apply to every PC.

Use the table to decide.

The honest answer is that fluid dictation is a convenience for a particular group: English speakers who dictate a lot and spend real time fixing their drafts. For everyone else, the free built-in tools do the job, and a Copilot+ PC should be chosen for other reasons. If privacy is the deciding factor, read our guide to Windows dictation privacy first, because the voice typing recognition is online whatever the chip.

Two questions remain open, and the sources do not settle them. The pages we read give no measured speed or accuracy gain for fluid dictation. They also do not say which architecture the dictation tools use. Both are good reasons to test on your own machine before buying.

For the three questions this guide answers directly, see what fluid dictation is in Windows 11, whether Windows Voice Access uses AI and whether dictation software works on Windows on Arm. For the wider picture, start at our overview of dictation on Windows, where each guide covers one part of the topic.