> This page is for version v1.3 (default).
> For other versions, use one of these documentation indexes:
> - v1.3 (default): https://docs.twelvelabs.io/v1.3/llms.txt

> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://docs.twelvelabs.io/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.twelvelabs.io/_mcp/server.

# Marengo 3.5

> Marengo 3.5 is an embedding model. It analyzes video, audio, images, and documents.

Marengo 3.5 is an embedding model for comprehensive video understanding. It analyzes video, audio, images, and documents, then combines their visual, audio, and text information. This provides a holistic understanding similar to human comprehension.

Marengo 3.5 produces embeddings of 128, 256, or 512 dimensions. Shorter embeddings reduce the size of your index and speed up similarity search; longer embeddings produce higher retrieval quality.

> **Notes**
>
> * The `/search` endpoint does not support Marengo 3.5. To search your content with the platform, enable Marengo 3.0 for your index. To search Marengo 3.5 embeddings, query them in your own system.
> * Marengo 3.5 embeddings are not compatible with Marengo 3.0 embeddings. To move to Marengo 3.5, regenerate your embeddings with Marengo 3.5. For step-by-step instructions, see the [Migrate from Marengo 3.0 to Marengo 3.5](/v1.3/docs/get-started/migration-guides/marengo-3-0-to-3-5) guide.

# New in Marengo 3.5

Compared to Marengo 3.0, Marengo 3.5 adds the following capabilities:

| Capability                         | Marengo 3.5                                                           | Marengo 3.0                      |
| ---------------------------------- | --------------------------------------------------------------------- | -------------------------------- |
| Document inputs                    | PDF, plain text, and Markdown files                                   | Not available                    |
| Embedding dimensions               | 128, 256, or 512, selectable per request                              | Fixed at 512                     |
| Video and audio duration           | No limit                                                              | Up to 4 hours                    |
| Composed queries across modalities | Combine text with images, video, or audio                             | Combine text with images         |
| Audio track                        | Unified encoder for speech, music, and non-dialog audio               | Separate transcription embedding |
| Embedding uncertainty              | Per-dimension uncertainty vector; higher value shows lower confidence | Not available                    |
| Time-based metadata fusion         | Supported                                                             | Not available                    |

# Use cases

Create embeddings from video, audio, images, and documents. Use these embeddings for similarity search, content classification, clustering, recommendations, or Retrieval-Augmented Generation (RAG).

The platform provides two ways to create embeddings. To embed a query, the platform processes your request synchronously and returns the embedding in the response. To embed content at scale, the platform processes your media files asynchronously, one file per request. For details, see the [Embed a query](/v1.3/docs/guides/create-embeddings/query) and [Embed content at scale](/v1.3/docs/guides/create-embeddings/at-scale) guides.

# Input requirements

The specifications on this page reflect the maximum capabilities of the model. Your actual requirements depend on the upload method and operation you choose. For details about the available upload methods and the corresponding limits, see the [Upload and processing methods](/v1.3/docs/concepts/upload-methods) page.

## Video file requirements

* **Duration**: 4 sec or longer
* **File size**: No model limit. Your upload method sets the effective limit.
* **Resolution**: 360x360 to 5184x2160
* **Aspect ratio**: Between 1:1 and 1:2.4, or between 2.4:1 and 1:1. For example, you can use 1:1, 4:3, 4:5, 5:4, 16:9, 9:16, or 17:9.
* **Formats**: [FFmpeg supported](https://ffmpeg.org/ffmpeg-formats.html)

> **Notes**
>
> * If you upload files using publicly accessible URLs, use direct links to raw videos that play without user interaction or custom video players (example: `https://example.com/videos/sample-video.mp4`). Video hosting platforms and cloud storage sharing links are not supported.
>
> * For videos in other formats or if you require different options, contact us at [support@twelvelabs.io](mailto:support@twelvelabs.io).

## Image file requirements

* **Formats**: JPEG, PNG
* **Minimum size**: 128x128 pixels
* **File size**: ≤ 32 MB

## Audio file requirements

* **Formats**: WAV (uncompressed), MP3 (lossy), and FLAC (lossless)
* **Duration**: No limit
* **File size**: No model limit. Your upload method sets the effective limit.

## Document file requirements

* **Formats**: PDF (`.pdf`), plain text (`.txt`), and Markdown (`.md`)
* **File size**: ≤ 512 MB
* **Pages**: A PDF file has a page allowance of 16 pages for each MB of file size when you embed a query, and 64 pages for each MB when you embed content at scale. A file smaller than 1 MB has the same allowance as a 1 MB file. Plain text and Markdown files have no page allowance.

# Supported languages

Marengo 3.5 supports the following languages:

Arabic, Bengali, Chinese (Simplified), Croatian, Cusco, Czech, Danish, Dutch, English, Farsi, Filipino, Finnish, French, German, Greek, Hebrew, Hindi, Hungarian, Indonesian, Italian, Japanese, Korean, Maori, Norwegian, Polish, Portuguese, Romanian, Russian, Spanish, Swahili, Swedish, Telugu, Thai, Turkish, Ukrainian, and Vietnamese.

# Support

For support or feedback regarding Marengo, contact [support@twelvelabs.io](mailto:support@twelvelabs.io).