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

Details

Model IDbfl/flux-2-klein-4b

ProviderVercel AI Gateway

CreatorBlack Forest Labs

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

Pricing

Input

Output

Cache write

—

Cache read

—

Batch in

—

Batch out

—

API

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

flux-2-klein-4b

bfl/flux-2-klein-4b

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

Changes · 2 entries

bfl/flux-2-klein-4bupdate2b100acMar 23, 2026, 05:30 AM

model_typeimage

parameters4

bfl/flux-2-klein-4bcreateb50649fMar 21, 2026, 11:58 PM