flux-2-klein-4b

Name: flux-2-klein-4b
Author: Vercel AI Gateway

imageapache-2.04B

Lightweight 4B-parameter FLUX.2 flow model for sub-second inference; ~13 GB VRAM. Open base weights under Apache 2.0.

Input price

$0/1M tokens

Output price

$0/1M tokens

Capabilities

Show unsupported (14)

Infrastructure

Streaming

Fine-tuning

Model IDbfl/flux-2-klein-4b

Family—

Licenseapache-2.0

Statusactive

Typeimage

Input modalitiestext

Output modalitiesimage

Open weightYes

Parameters4B

Architecture—

Max resolution—

Resolutions—

Aspect ratios—

Batch size—

Release date2026-01-15

Sourceofficial

Input

Output

Cache write

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Cache read

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Batch in

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Batch out

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GET/v1/models/vercel/bfl/flux-2-klein-4b