Flux API key: two paths, and what changes after you have one

Flux Pro v1.1 runs upstream on fal. You can hold a key with the vendor directly, or one key that reaches Flux Pro v1.1 alongside the other models through a single interface. The tradeoffs are laid out in how to get an AI video API key — this page covers what changes once you have one.

What a call costs

5 credits at default settings, which is $0.05–$0.07 depending on your pack.

The constraint to know before you build

n caps at 4. Cost is linear, so batching buys concurrency slots rather than a discount.

Using it

export GENACE_API_KEY=sk_xxx

curl -X POST https://genace.ai/api/v1/images/generations \
  -H "Authorization: Bearer $GENACE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"flux-pro","prompt":"..."}'

Verifying the key costs nothing

curl https://genace.ai/api/v1/models -H "Authorization: Bearer $GENACE_API_KEY"

This authenticated read has no generation charge and skips generation concurrency checks, but its own request-rate limit still applies. A 200 means the key is live; anything else is covered in MISSING_API_KEY and INVALID_API_KEY.

Understand the quota scopes

Tier	Requests per minute	Concurrent jobs
Free	5	1
Pro	60	5

Request rate is enforced per API key; concurrent generation jobs are counted per user. A second key does not create another user concurrency allowance. Separate keys can still isolate credentials and key-specific spending caps.

Continue with models and parameters

• Flux API parameters: every accepted value and what it costs
• Flux aspect ratio options: what it accepts and what it rejects
• Flux resolution options and what they cost
• Browse all models and parameters guides

Models covered on this page

• FLUX Pro