---
license: apache-2.0
language:
  - en
tags:
  - text-to-image
  - flux
  - flux-2-klein
  - api
  - apimodels
---

# FLUX.2 Klein — hosted API access

This repository is **not the model weights** — it documents running **FLUX.2 Klein** through a
hosted API on **[apimodels.app](https://apimodels.app)**, a multi-model gateway where one key and one
OpenAI-compatible endpoint reach 110+ image, video, audio and language models.

- Original model & weights: **https://huggingface.co/black-forest-labs/FLUX.2-klein-4B**
- Authors: Black Forest Labs
- License: Apache-2.0 (FLUX.2 [klein] 4B)

Independent hosted-API integration. Not affiliated with or endorsed by the authors; does not
redistribute their weights. All credit for the model is theirs.

## What it does

The open, Apache-2.0 4B variant of Black Forest Labs’ FLUX.2 family. Text-to-image plus up to a few reference images.

![FLUX.2 Klein — hosted API access sample](sample-flux.png)

*A sample produced through the apimodels.app API.*

## Use it via API

On apimodels.app the model is served as **flux-2-klein-4b**. Get a key at https://apimodels.app, then:

```bash
# text-to-image (sync: pass a WxH size, get the image inline)
curl -X POST https://api.apimodels.app/v1/images/generations \
  -H "Authorization: Bearer YOUR_API_KEY" -H "Content-Type: application/json" \
  -d '{ "model": "flux-2-klein-4b", "prompt": "a cozy bookstore cafe, warm light", "size": "1360x768" }'
```

## Pricing

| Tier | Price |
| --- | --- |
| flux-2-klein-4b | $0.006 / image (flat) |
| each reference image | +$0.0015 (up to 3) |

Failed jobs are not charged. Result files are kept for 7 days.

## Links

- Run it: **[apimodels.app](https://apimodels.app)**
- Original model: https://huggingface.co/black-forest-labs/FLUX.2-klein-4B