---
title: "Alt Text Generator"
description: "Generate accessible alt text for images with vision AI."
keywords:
  - image alt text generator
  - accessibility alt text
url: "https://www.pixeltable.com/tools/alt-text-generator"
---

# Alt Text Generator

Generate accessible alt text for images with vision AI.

Free online tool by Pixeltable. Run it at https://www.pixeltable.com/tools/alt-text-generator (interactive, no sign-up).

## Features

- Vision LLM captions
- Accessibility-focused
- Free tier

## FAQ

### Why is alt text important?

Alt text improves accessibility for screen readers and can boost SEO for image-heavy pages.


## Fact sheet

Last updated 2026-09-23.

| Fact | Value |
| --- | --- |
| Modality | Image |
| Inputs | Image plus an instruction |
| Outputs | Model text about the image |
| Computed column | gemini.generate_content on the image and the prompt |
| What updates | A new or changed row recomputes only that row. Unchanged rows stay cached. |
| Canonical doc | [gemini.generate_content](https://docs.pixeltable.com/sdk/latest/gemini#udf-generate_content) |

```python
import pixeltable as pxt
from pixeltable.functions.gemini import generate_content

TableModel = pxt.model_base()

class Ocr(TableModel, name='ocr'):
    source_image: pxt.Image
    prompt: pxt.String

    vision_response = generate_content(
        contents=[source_image, prompt],
        model='gemini-2.5-flash',
    )
```