Pricing for adult/NSFW generation APIs is all over the map — subscriptions, credit packs, per-second video, per-image rates, and a few traps that make the sticker price misleading. This breaks down how the models price, what to watch for, and how Api18.dev’s pay-per-call billing works.
The pricing models you’ll see#
- Subscription tiers. A flat monthly fee for a quota. Cheap if you max it out, wasteful if you don’t, and a wall when you exceed it.
- Credit packs. Buy credits up front; watch for packs that expire or credits that don’t carry over.
- Pay-per-call. You pay for each generation and nothing else. Best aligned with actual usage.
What to watch for#
- Minimums. Some APIs require a monthly floor. Pay-per-call with no minimum avoids it.
- Failed-job charges. You shouldn’t pay for output you didn’t get. On Api18.dev, failed jobs are refunded automatically.
- Resolution/duration multipliers. Video especially scales with resolution and length — read the per-second rate, not just the headline.
- Payment lock-in. Forced card-on-file is friction (and a privacy issue for adult work). USDT avoids it.
How Api18.dev prices#
- Images: per image, in USD (×
num_imageswhere supported). - Image editing: per run, in USD.
- Video: per second of output, in USD, by resolution × duration.
- No subscription, no minimums. Failed calls are free.
The exact, current rate for every model is shown on the pricing section and each model’s docs page — derived from the live registry, so it never drifts from what you’re actually charged.
The $10 welcome credit lets you measure real per-call cost on your own prompts in the playground before committing a cent.
Estimating your monthly cost#
Multiply your expected calls by the per-call rate of the models you’ll use. Because billing is per call, your cost scales linearly with usage — no tier cliffs. Fund it in USDT on Solana or Tron and top up as you grow. More on payments in Pay-per-call with crypto.