FeaturesMultimodal

Multimodal Capabilities

Send images, PDFs, and audio to OpenRouter models

OpenRouter supports multiple input modalities beyond text, allowing you to send images, PDFs, and audio files to compatible models through our unified API. This enables rich multimodal interactions for a wide variety of use cases.

Supported Modalities

Images

Send images to vision-capable models for analysis, description, OCR, and more. OpenRouter supports multiple image formats and both URL-based and base64-encoded images.

Learn more about image inputs →

PDFs

Process PDF documents with any model on OpenRouter. Our intelligent PDF parsing system extracts text and handles both text-based and scanned documents.

Learn more about PDF processing →

Audio

Send audio files to speech-capable models for transcription, analysis, and processing. OpenRouter supports common audio formats with automatic routing to compatible models.

Learn more about audio inputs →

Getting Started

All multimodal inputs use the same /api/v1/chat/completions endpoint with the messages parameter. Different content types are specified in the message content array:

  • Images: Use image_url content type
  • PDFs: Use file content type with PDF data
  • Audio: Use input_audio content type

You can combine multiple modalities in a single request, and the number of files you can send varies by provider and model.

Model Compatibility

Not all models support every modality. OpenRouter automatically filters available models based on your request content:

  • Vision models: Required for image processing
  • File-compatible models: Can process PDFs natively or through our parsing system
  • Audio-capable models: Required for audio input processing

Use our Models page to find models that support your desired input modalities.

Input Format Support

OpenRouter supports both direct URLs and base64-encoded data for multimodal inputs:

URLs (Recommended for public content)

  • Images: https://example.com/image.jpg
  • PDFs: https://example.com/document.pdf
  • Audio: Not supported via URL (base64 only)

Base64 Encoding (Required for local files)

  • Images: data:image/jpeg;base64,{base64_data}
  • PDFs: data:application/pdf;base64,{base64_data}
  • Audio: Raw base64 string with format specification

URLs are more efficient for large files as they don’t require local encoding and reduce request payload size. Base64 encoding is required for local files or when the content is not publicly accessible.

Frequently Asked Questions

Yes! You can send text, images, PDFs, and audio in the same request. The model will process all inputs together.

  • Images: Typically priced per image or as input tokens
  • PDFs: Free text extraction, paid OCR processing, or native model pricing
  • Audio: Priced as input tokens based on duration

Video modality support is coming soon! We’re working on adding video processing capabilities to expand our multimodal offerings.