Billing and pricing

API billing is purely usage-based: there is no base fee, no per-seat charge, and no minimum. Each request is metered against the model it uses, your free credit absorbs cost first, and only usage beyond the credit is billed to your payment method.

1. Every metered request records a usage event: the model used, the quantity in seconds, and the cost at that model's hourly rate, rounded up to the next cent.
2. Remaining free credit is applied to each event first. While credit remains, nothing is billed.
3. Once credit is exhausted, usage above it is charged to the payment method on file and invoiced through your metered subscription.
4. Usage accumulates per calendar month; the period field in usage responses is formatted YYYYMM.

Pre-recorded models meter the duration of the source audio. Realtime and voice agent models meter session connection time, from WebSocket open to close.

For long jobs you can pass estimated_duration_sec when creating a transcript or session token. The API then checks the estimate against your remaining credit up front and rejects the request with 402 instead of letting it fail midway.

Rates are also served live by GET /v2/pricing, which is the recommended source if you display pricing to your own users.

The $10 credit is granted once per account and never expires. Check your balance any time with GET /v2/credits; the credit_balance_cents field is what remains.

When the balance reaches zero and no payment method is on file, metered endpoints stop accepting new work and return 402 Payment Required with the error code v2_billing_required. Existing transcripts remain readable; only new metered requests are blocked. Add a payment method through checkout to continue.

Start a secure hosted checkout to attach a payment method and activate metered billing. The endpoint returns a URL; open it in a browser to complete setup. Afterwards, usage beyond your remaining credit is billed automatically.

curl -X POST https://api.realtimevoicekit.com/v2/billing/checkout \
  -H "Authorization: Bearer rtvk_your_api_key"

# {"url": "https://checkout..."}  Open this URL to add a payment method.

You can also start checkout from the API dashboard. If a metered subscription is already active, the endpoint returns 409 with code already_api_subscribed.

Three read endpoints expose everything you need for cost dashboards and alerts:

curl https://api.realtimevoicekit.com/v2/credits \
  -H "Authorization: Bearer rtvk_your_api_key"

All monetary fields are integers in USD cents. The GET /v2/credits response contains:

Each event from GET /v2/usage includes the sku (model id), unit_type, quantity in seconds, retail_cost_cents, credit_applied_cents, billable_cents, and created_at, so you can attribute every cent to a specific transcript or session.

• Compare models and rates before choosing a default.
• Create an API key and make a first request.
• Read the FAQ for common billing questions.