---
title: "OpenRouter Tutorial: How to Send an Image to an LLM via API (Vision Guide)"
source: "OpenRouter：Announcements（RSS）"
source_tier: "t1"
url: "https://openrouter.ai/blog/tutorials/send-image-to-llm/"
permalink: "https://feed.astralor.com/items/itm_f0114da50833fe89c323c17d"
published: "2026-08-14T00:00:00.000Z"
score: 79
channel: "ai"
tags: ["OpenRouter","RAG","Multimodal API","Vision Model"]
---

# OpenRouter Tutorial: How to Send an Image to an LLM via API (Vision Guide)

## AI commentary

> The main value of this tutorial is that it unifies image transmission across different providers into one standard, saving developers from adaptating per model. Especially useful for those building agents or multimodal applications.

## At a glance

OpenRouter's official guide explains how to send images to any vision-capable LLM using a unified request format. It covers base64 vs hosted URLs, model selection, multiple images, tokenization, and multimodal RAG, helping developers quickly adopt multimodal API calls.

## Key points

- Send images with a single request shape: a content array containing both text and image_url parts, shared by all vision models.
- Compares base64 embedding vs hosted URLs, with recommendations on when to use each.
- Covers multi-image input, tokenization, and building multimodal RAG pipelines.

## Full text

Send images to any vision-capable LLM with one request shape: a content array with a text part and an image_url part. Covers base64 vs hosted URLs, model selection, multiple images, tokenization, and multimodal RAG.

---

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