FLUX Klein 2 4B Base
FLUX Klein 2 4B Base is Black Forest Labs's image generation model. The base (non-fine-tuned) variant of the compact 4B FLUX Klein 2 model, suitable as a foundation for downstream image generation tasks.
| Specifications | |
|---|---|
black-forest-labs-flux-klein-2-4b-base | |
| Image Generation | |
| Active | |
| Black Forest Labs | |
| Text | |
| Image | |
| 4B | |
| Benchmarks | |
|---|---|
| Elo Rating | 964#287 |
Capabilities
Input1/5
Text✓
Image·
Audio·
Video·
PDF·
Output1/5
Text·
Image✓
Audio·
Video·
Embedding·
Capabilities0/13
Reasoning·
Adaptive Reasoning·
Function Calling·
Parallel Function Calling·
Structured Outputs·
Native JSON Schema·
Web Search·
URL Context·
Computer Use·
Code Execution·
File Search·
Prompt Caching·
Assistant Prefill·
Cheapest Instances to Run It
Cloud GPU instances that can host FLUX Klein 2 4B Base, ranked by cheapest on-demand price. The model needs about 10 GB of GPU memory at FP16 precision (estimated from its parameter count), so treat the fit as guidance rather than a guarantee.
All clouds
FP16 (full precision)
US Dollar ($)
Instance | Cloud | GPU | VRAM | Price | Cheapest region | |
|---|---|---|---|---|---|---|
| Standard_NV4as_v4 |  Azure | AMD Radeon Instinct MI25 | 16 GB | $0.233/hr | westus2 | |
| g5g.xlarge |  AWS | T4g | 16 GB | $0.420/hr | us-east-1 | |
| Standard_NV8as_v4 | Azure | AMD Radeon Instinct MI25 | 16 GB | $0.466/hr | westus2 | |
Versions
| Version | Released | Context | Input / 1M | Output / 1M | Status |
|---|---|---|---|---|---|
| FLUX Klein 2 4B | — | — | — | Available | |
| FLUX Klein 2 9B | — | — | — | Available | |
| FLUX 2 Max | 67K | — | — | Available | |
| FLUX 2 Flex | — | — | — | Available | |
| FLUX Klein 2 4B Base | — | — | — | — | Current |
| FLUX 2 Dev | — | — | — | — | Available |
| FLUX 2 Dev Flash | — | — | — | — | Available |
| FLUX 2 Dev Turbo | — | — | — | — | Available |
| FLUX Klein 2 9B Base | — | — | — | — | Available |
| FLUX.1 Fill Pro | — | — | — | Available | |
| FLUX.1 Dev | — | 4K | $0.100 | $0.100 | Available |