Testzilla® / Voice AI Billing Audit
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Free Retell & VAPI billing audit

How much money is your voice agent wasting?

Paste your Retell or VAPI key below and find out in under a minute. We break down three months of calls by product, month, week and day, and price every avoidable cost to the year. Your key never leaves your browser.

You will see more about where your money goes than your own platform console shows you.

Retell keys start key_ and live under API Keys in the Retell dashboard. VAPI private keys are the UUID under API Keys in the VAPI dashboard. We work out which is which from the key itself. Only aggregate call data is reported — no transcripts or recordings are accessed in any way. You can revoke the key in your dashboard the moment the scan finishes. Please only paste a key you are authorised to use.

Your API key never leaves this browser

What you get — a sample report, with illustrative numbers:

The money leak

$2,473

a year in avoidable charges we can take off this bill.

The biggest single leak: 2,254 of 2,885 calls carried a prompt over Retell's 4,000 token threshold and were surcharged for it. That is 42.1% of the bill, spent on nothing.

Surcharge this month$260.18
Surcharge, 97 days$511.16
Total spend, 97 days$1,216
Surcharge alone$1,932 /yr

Plus the full evidence: daily spend by product, month/week/day breakdowns, engine mix, and a per-finding fix list — all from your own billing records.

Want a closer look?

This audit reads your bill. If you want the rest of the picture — what your agents and conversation flows actually do, where the cost really comes from, and the kind of visualizations and drill-downs you cannot get from a platform console — that is what we do all day.

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