---
id: "black-forest-labs/flux.2-klein-4b"
also: ["black-forest-labs/flux.2-klein-4b", "black-forest-labs/FLUX.2-klein-4B", "vercel/bfl/flux-2-klein-4b"]
card_usd_per_m: "0.0 in, 0.0 out, at black-forest-labs"
context: 40960
max_output: 36864
input: ["text", "image"]
output: ["image"]
released: "2026-01-14"
api: ["/api/v1/images"]
params: ["max_tokens", "seed", "stop", "temperature"]
endpoints: 2
gateways: "openrouter (1), vercel (1)"
no_training: 1
trains: 0
retains_prompts: 1
---
# Black Forest Labs: FLUX.2 Klein 4B

FLUX.2 \[klein\] is Black Forest Labs' fastest image model yet - it unifies image generation and editing in a single, compact model. Delivering state-of-the-art quality with end-to-end inference in less than a second. Enabling interactive workflows, real-time previews, and latency-critical applications.