# Troubleshooting the AI assistant and Gemini Nano

:::callout
**Is the AI assistant in Admin Tools not working, or do you see "Gemini AI is not available in this browser"?** The AI runs on Gemini Nano, the model that Chrome executes locally on your device. Nothing goes to a server. Below you fix the most common problems.
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## System requirements

:::info title="What Gemini Nano needs"
Chrome 138 or newer on a desktop with Windows, macOS or Linux, at least 22 GB of free disk space for the model, and preferably 16 GB of RAM. A managed corporate or school profile can block the required flags.
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## "Gemini AI is not available in this browser"

:::warn
**Cause.** The required Chrome flag is missing. You are on a Chrome version below 138 or on an unsupported platform such as mobile.
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:::howto title="Restore availability"
1. Check your version at chrome://settings/help and update Chrome to at least 138.
2. Use a desktop build. Gemini Nano does not work on Chrome for Android or iOS.
3. Open chrome://flags and enable the AI flags as described in the activation guide.
4. Fully restart Chrome after changing the flags.
:::

## "Availability returns unavailable, even after restart"

:::warn
**Cause.** The flag is set correctly, but the model is rejected. Usually because of too little disk space, a GPU that is too old, or a locked profile.
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:::howto title="Fix unavailable"
1. Free up disk space. Gemini Nano refuses to download when less than 22 GB is free.
2. Set "Enables optimization guide on device" to "Enabled BypassPerfRequirement", not just "Enabled". That bypasses the performance gate on older integrated GPUs.
3. Use a personal account. Corporate and school profiles often have the flag policy-locked.
4. Restart Chrome and check availability again.
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## "The model download never finishes"

:::warn
**Cause.** chrome://components shows 0.0.0.0 for "Optimization Guide On Device Model", the download does not start.
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:::howto title="Kick off the download"
1. Open chrome://components and click Check for update next to "Optimization Guide On Device Model".
2. Close tabs that use the AI APIs.
3. Restart Chrome.
4. If that does not help, temporarily disable your VPN or ad-blocker. Some privacy extensions block the Google update servers.
:::

## "Responses are slow or Chrome freezes"

:::warn
**Cause.** On a machine with little memory the model competes with your normal browsing.
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:::howto title="Improve speed"
1. Close unnecessary tabs and programs, especially on a machine with 8 GB of RAM.
2. Keep in mind that the first prompt is slow while Chrome downloads the roughly 22 GB model in the background. After that everything runs locally.
3. Expect a latency of 100 to 400 ms per token. A full paragraph takes two to four seconds, which is normal.
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## "My antivirus quarantined the model files"

:::warn
**Cause.** Some corporate endpoint security products quarantine the model files.
:::

:::howto title="Release the model files"
1. Find the OptGuideOnDeviceModel folder under the Chrome user data directory.
2. Add that path to your antivirus allowlist.
3. Let Chrome fetch the model again through Check for update in chrome://components.
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## Frequently asked questions

:::faq
### Does Gemini Nano work offline once downloaded?
Yes. After the initial download no network is required.

### Is my data sent to Google?
No. The model runs fully on your device. Google may still receive ordinary Chrome telemetry and crash reports, but your prompts and their responses are not included.

### Can I use Gemini Nano outside Chrome?
Not directly. The model ships as a Chrome component and only the browser APIs expose it.

### What happens if I disable the flags later?
The model files remain on disk but the APIs are no longer available. You can delete the files manually from OptGuideOnDeviceModel to reclaim the space.

### Is Gemini Nano the same as Gemini 1.5 Flash or Pro?
No. Nano is a separate, much smaller model for on-device processing. For simple tasks quality is close to Flash, but it does not match Pro on complex reasoning.

### Which languages does Gemini Nano support?
English is the strongest. Dutch, German, French, Spanish, Italian and several other European languages are usable but noticeably weaker. The Translator API covers many more languages.
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