Image model vs image model
FLUX.1 Dev vs FLUX.2 Klein 4B
People rate their pictures about the same in blind votes, so the cheaper FLUX.2 Klein 4B is the better buy: $0.025 against $0.005 an image.
At a glance
Longer bar means the bigger number. Elo bars start at 800.
Price per image · 1024×1024, lower is better
Text to image · arena Elo, higher is better
Where they sit among all 56 image models
Up and to the left is better pictures for less money. Hover or tap a dot for its numbers, then click it to compare that model with FLUX.1 Dev. Models the arena hasn’t rated yet sit in the grey lane at the bottom.
Which one to pick
Pick FLUX.2 Klein 4B if
- price matters: 100 images cost $0.50, against $2.50 with FLUX.1 Dev
- you need to edit pictures you upload; FLUX.1 Dev only makes new ones here
The specs
| Spec | FLUX.1 Dev | FLUX.2 Klein 4B |
|---|---|---|
| Price per image | $0.025 | $0.005 ($0.02 per edit) |
| 100 images | $2.50 | $0.50 |
| Text-to-image Elo | 823 ±45 (#100 in the arena) | 837 ±12 (#96 in the arena) |
| Editing Elo | Not scored yet | 938 ±17 (#62 in the arena) |
| Arena votes | 511 | 6,418 |
| Edits uploaded pictures | No | Yes |
| Largest size | — | — |
| Open weights | Yes | Yes |
| Zero data retention | — | — |
| Lab | Black Forest Labs | Black Forest Labs |
| Official name | FLUX.1 [dev] | FLUX.2 [klein] 4B |
| Released | August 2024 | January 2026 |
Elo ± is the 95% margin. Prices are for one 1024×1024 image from fal.ai.
Questions
Which is better, FLUX.1 Dev or FLUX.2 Klein 4B?
People rate their pictures about the same in blind votes, so the cheaper FLUX.2 Klein 4B is the better buy: $0.025 against $0.005 an image.
Which is cheaper, FLUX.1 Dev or FLUX.2 Klein 4B?
FLUX.2 Klein 4B: $0.005 for a 1024×1024 image, against $0.025 for FLUX.1 Dev. 100 images cost $0.50 and $2.50.
Can FLUX.1 Dev and FLUX.2 Klein 4B edit images?
FLUX.2 Klein 4B can change a picture you upload. FLUX.1 Dev only makes new pictures from a prompt here.
How can I compare FLUX.1 Dev and FLUX.2 Klein 4B myself?
Open the comparison, type one prompt and both models draw it side by side, each with what it cost and how long it took. You sign up with Google before your first run, and new accounts start with free credit.
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Where the numbers come from
Quality scores are Elo ratings from the Artificial Analysis image arenas, where people vote between two pictures made from the same prompt without knowing which model made which. The vote split comes from the Elo gap. Prices are for one 1024×1024 image from fal.ai; models billed per token are estimated at the quality the arena scored. The sample pictures are our own runs. Updated October 25, 2026.