Which AI API doesn't require an upfront fee? Most token-based vendors are pay-as-you-go: add a card, pay for usage, no annual commit. Flat-rate APIs like Daymora charge $25/month upfront but remove token math.
Pay-as-you-go (metered)
Pros: start at near-zero, scale spend with usage, no commit.
Cons: unpredictable invoices, finance overhead, incentive to cripple prompts.
Best for experiments and pass-through billing (true cost).
Flat subscription (no per-token line item)
Pros: predictable budget, simpler mental model for prod (what is flat-rate).
Cons: not ideal for months with literally zero calls.
Free tiers (no upfront cash)
Some accounts start with credits — see free tier comparison and no credit card options.
Choosing
| Situation | Pick |
|---|---|
| Hackathon | Free / pay-go |
| SaaS core feature | Flat-rate or capped enterprise |
| Agency pass-through | Pay-go |
Bottom line
"No upfront fee" usually means metered tokens. That is flexible early and expensive emotionally later — plan the transition when logs show steady traffic.