2026-08-24 · Scarleta Engineering

You should never pay twice to analyze the same file

Owner-scoped content-hash caching plus transparent per-second prepaid pricing: understand a file once, and don't get charged to understand it again.

Here's a small injustice that most metered APIs quietly commit: you send the same file twice, and you pay twice. Nothing about the audio changed. The answer is identical. But the meter runs again.

We think that's wrong, so we built the platform not to do it.

Understand a file once

Every piece of audio has a content hash, a fingerprint derived from the bytes themselves. When you submit a file for analysis, we key the result by that fingerprint. Resubmit the same audio and we reuse the result we already computed instead of re-running the work and re-charging you.

One important honesty note: this reuse is owner-scoped. The cache is keyed by the content fingerprint and the owner, so a file you already analyzed in your account isn't re-analyzed or re-charged for your account. Results are not shared or reused across different accounts. It's "don't charge me twice for my own file," not "everyone shares one global cache."

Transparent, per-second, prepaid

The pricing model is deliberately boring, which is a compliment. You pay per second of audio: one token equals one second, priced at ten cents per minute. You top up a prepaid balance and draw it down as you work. There's no subscription and no seat to buy. Top-ups only, with conveniences like a saved card, low-balance alerts, and optional auto-recharge when your balance runs low.

A few concrete facts, because vague pricing is its own kind of overcharge:

  • One token = one second of audio, at $0.10 per minute.
  • Minimum one token per job : the smallest possible charge is well-defined.
  • Cropping a file is free : no token charge to trim to the part you want.
  • New accounts start with a one-time grant of 300 tokens to try things out.
  • The minimum top-up is $10.

Why "never pay twice" is a principle, not a promo

Caching and honest pricing sound like billing trivia. They're actually a statement about who the platform is for. A tool that re-charges you for identical work is optimizing for its own revenue. A tool that refuses to is optimizing for your trust, betting that trust is the more valuable thing to earn.

Understand a file once. Pay for it once. Keep the rest of your balance for work you actually haven't done yet.


Owner-scoped content-hash caching and per-second prepaid pricing (300-token free grant, $10 minimum top-up, free cropping, saved card, auto-recharge, low-balance alerts) are live. See Pricing.

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