FLUX.2 Klein 4B
Summary
FLUX.2 Klein 4B is an open-weight image generation model from Black Forest Labs, released on 14 Jan 2026. It accepts images and text and generates images, with a 41K-token context window and up to 41K output tokens per response.
Image model for prompt-driven generation, editing, and visual design workflows
Last verified 21 Oct 2026. Every figure on this page links to its source.
Specifications
| Developer | Black Forest Labs |
|---|---|
| Release date | 14 Jan 2026 [models.dev] |
| Status | Generally available [models.dev] |
| Weights | Open weights [models.dev] |
| Context window | 41K (40,960 tokens) [models.dev] |
| Max output | 41K tokens [models.dev] |
| Knowledge cutoff | Jun 2025 [models.dev] |
| Input | Images and text [models.dev] |
| Output | Images [models.dev] |
| Reasoning mode | No [models.dev] |
| Tool calling | No [models.dev] |
FLUX.2 Klein 4B API pricing by provider
USD per million tokens. Sorted by input price.
| Provider | Input | Output | Cached input | Context | Source |
|---|---|---|---|---|---|
| NVIDIA NIM black-forest-labs/flux_2-klein-4b | Free | Free | – | 41K | models.dev, 21 Oct 2026 |
| Vercel AI Gateway bfl/flux-2-klein-4b | – | – | – | – | models.dev, 21 Oct 2026 |
Frequently asked questions
What is the context window of FLUX.2 Klein 4B?
FLUX.2 Klein 4B has a context window of 40,960 tokens (41K) and can generate up to 40,960 tokens in a single response, according to models.dev.
Is FLUX.2 Klein 4B open source?
FLUX.2 Klein 4B is an open-weight model. Check the license terms before commercial use.
When was FLUX.2 Klein 4B released?
Black Forest Labs released FLUX.2 Klein 4B on 14 Jan 2026, according to models.dev.
Which providers offer FLUX.2 Klein 4B?
We track FLUX.2 Klein 4B on 2 providers: NVIDIA NIM, Vercel AI Gateway.
Change history
- Added to the directory
- Now listed on Vercel AI Gateway
- Now listed on NVIDIA NIM