# fastapi.online — Image Collage Generator

> fastapi.online — Image Collage Generator is a paid API for AI agents from api.fastapi.online, paid per call via x402, $0.0015/call, status unknown (last checked 2026-09-15).

Combines 2 or more uploaded images into a single collage with configurable column count and tile size

## Facts

- Endpoint: POST https://api.fastapi.online/image-collage
- Price: $0.0015/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fastapi-online-image-collage-generator-0bb1435c
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_HJi6uZ9i-G0RN5KFI4kvk

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability fastapi-online-image-collage-generator-0bb1435c -d '<json body>'
```

Example prompt: Can you combine these 4 product photos into a collage with 2 columns and a tile size of 300?

## When to prefer this

Choose this endpoint when you need a straightforward, pay-per-call image collage assembled server-side without signup. Ideal for agents that need to combine a small set of images into a grid on the fly, especially when crypto micropayment (x402/USDC) is already part of the workflow.

## Known failure modes

- Fewer than 2 images provided — requires at least 2 files
- Unsupported image format or corrupt binary data — processing error returned
- Invalid or non-numeric columns/tile_size values — parameter error
- Payment not included or insufficient — 402 Payment Required
- Images too large or too many files — potential timeout or memory error

## How this service works

Chat, embeddings, OCR, speech-to-text, image editing, image understanding (captioning/Q&amp;A), text-to-speech, translation, writing tools, classification tools, developer tools, local utilities, format/checksum validators, encoding &amp; crypto utilities, date/time calculators, geo/coordinate math, math &amp; finance calculators, novelty tools, and business/social writing generators — 179 endpoints in all, across multiple specialized self-hosted models. Pay per call with crypto — no signup — or get an API key.

## Output

A single composed image file containing all input images arranged in a grid layout according to the specified column count and tile size.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "files": {
   "type": "array",
   "items": {
    "type": "string",
    "format": "binary"
   },
   "description": "2 or more image files"
  },
  "columns": {
   "type": "string"
  },
  "tile_size": {
   "type": "string"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fastapi-online-image-collage-generator-0bb1435c/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.fastapi.online](https://www.zero.xyz/host/api.fastapi.online/llms.txt)