flux-2-klein-4b by Cloudflare Workers AI

Every Cloudflare account gets 10,000 neurons a day free across all Workers AI models, reset at 00:00 UTC. Create an API token with Workers AI permission and call the OpenAI-compatible endpoint with your account ID.

Access
Free API tier
Free limits
10K neurons/day (shared)
Modality
image
Credit card
Not required
Commercial use
Unclear, verify
Model ID
@cf/black-forest-labs/flux-2-klein-4b
Base URL
https://api.cloudflare.com/client/v4/accounts/{account_id}/ai/v1
Checked
Nov 11, 2026

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Frequently asked

Is flux-2-klein-4b free?

Yes. Cloudflare Workers AI offers it as Free API tier with these limits: 10K neurons/day (shared). No credit card is required.

Can I use flux-2-klein-4b commercially?

Commercial terms are not clearly documented. Check the provider's current terms before shipping.

How do I start using flux-2-klein-4b?

Get a free API key from the provider dashboard. Set the base URL to https://api.cloudflare.com/client/v4/accounts/{account_id}/ai/v1 and the model to @cf/black-forest-labs/flux-2-klein-4b. Every Cloudflare account gets 10,000 neurons a day free across all Workers AI models, reset at 00:00 UTC. Create an API token with Workers AI permission and call the OpenAI-compatible endpoint with your account ID.

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