Endpoints

Account and billing

Models and pricing, credit balance, usage events and summaries, and pay-as-you-go checkout.

These endpoints report what the API offers and what your account has consumed. Amounts are integer cents (USD); quantities are metered seconds of audio or session time; rates are quoted per hour.

Models and pricing

GET/v2/modelsList available models with rates. No authentication required.

GET/v2/pricingAlias of /v2/models. No authentication required.

Both endpoints return the same catalog: { "data": [ …model objects… ] }. Each model object has id, name, family, unit_type, rate_usd, and description. The endpoint is the authoritative source for rates; the table below shows the current catalog.

Model id	Family	Unit	Rate (USD)	Use for
whisper-voicekit-best	pre_recorded_stt	audio_hour	0.252	Highest-accuracy pre-recorded transcription for the core languages.
whisper-voicekit-fast	pre_recorded_stt	audio_hour	0.18	Cost-effective pre-recorded transcription with broad language coverage.
whisper-voicekit-realtime-pro	realtime_stt	session_hour	0.54	Low-latency realtime transcription for production voice workflows.
whisper-voicekit-realtime	realtime_stt	session_hour	0.18	Cost-effective realtime transcription sessions.
whisper-voicekit-agent	voice_agents	session_hour	5.40	Realtime voice agent sessions with speech, reasoning, and audio output.

Legacy model ids without the whisper- prefix (for example voicekit-best) still resolve to the same models for backward compatibility. Use the whisper-voicekit-… ids in new code.

List models

curl https://api.realtimevoicekit.com/v2/models

Credits

GET/v2/creditsYour free credit, remaining balance, and lifetime usage

Every account receives 10 USD of free API credit. Usage draws the credit down first; once it hits zero, cost-incurring requests return 402 v2_billing_required until a subscription is active.

Field	Type	Description
free_credit_cents	integer	The initial free credit, currently `1000` (10 USD).
credit_balance_cents	integer	Remaining credit in cents.
lifetime_retail_cents	integer	Total retail value of everything you have ever used.
lifetime_billable_cents	integer	Total amount actually billable after credits, lifetime.
period_billable_cents	integer	Billable amount in the current calendar month.
period	string	The current billing period as `YYYYMM`, for example `202607`.
subscribed	boolean	Whether a pay-as-you-go API subscription is active.

Check your balance

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

Example response

{
  "free_credit_cents": 1000,
  "credit_balance_cents": 742,
  "lifetime_retail_cents": 258,
  "lifetime_billable_cents": 0,
  "period_billable_cents": 0,
  "period": "202607",
  "subscribed": false
}

Usage events

GET/v2/usagePer-request usage events, newest first

Query param	Type	Default	Description
limit	integer, 1 to 200	50	Rows per page.
offset	integer, 0 or more	0	Rows to skip.

Returns { "data": [ …usage events… ] } with one event per metered unit of work.

Field	Type	Description
id	string	Usage event id.
transcript_id	string or null	The transcript this event belongs to, when applicable. Realtime and voice agent sessions have no transcript id.
sku	string	The model id that was metered.
unit_type	string	`audio_hour` or `session_hour`.
quantity	integer	Metered quantity in seconds of audio or session time.
retail_cost_cents	integer	Retail cost of the event in cents.
credit_applied_cents	integer	How much of the cost was covered by free credit.
billable_cents	integer	The remainder actually billed.
currency	string	Always `usd`.
stripe_metered	boolean	Whether the billable amount was reported to the payment processor.
created_at	string	ISO 8601 event time.

List recent usage

curl "https://api.realtimevoicekit.com/v2/usage?limit=20" \
  -H "Authorization: Bearer rtvk_your_api_key"

Usage summary

GET/v2/usage/summaryCredits plus usage totals grouped by product

Returns a credits object (same shape as GET /v2/credits) and a products array with one roll-up per model you have used: sku, name, family, unit_type, and summed quantity, retail_cost_cents, credit_applied_cents, and billable_cents.

Get the summary

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

Example response

{
  "credits": {
    "free_credit_cents": 1000,
    "credit_balance_cents": 742,
    "lifetime_retail_cents": 258,
    "lifetime_billable_cents": 0,
    "period_billable_cents": 0,
    "period": "202607",
    "subscribed": false
  },
  "products": [
    {
      "sku": "whisper-voicekit-best",
      "name": "Whisper VoiceKit Best",
      "family": "pre_recorded_stt",
      "unit_type": "audio_hour",
      "quantity": 36840,
      "retail_cost_cents": 258,
      "credit_applied_cents": 258,
      "billable_cents": 0
    }
  ]
}

Billing checkout

POST/v2/billing/checkoutStart a pay-as-you-go API subscription

Creates a hosted checkout session for the pay-as-you-go API subscription and returns its URL. Open the URL in a browser to complete payment setup; once the subscription is active, usage beyond your free credit is metered and billed automatically, and subscribed flips to true on GET /v2/credits.

Response field	Type	Description
url	string	The hosted checkout URL to open in a browser.

Status	Code	When
409	already_api_subscribed	An API subscription is already active on this account.
502	stripe_error	The payment provider did not return a checkout URL.
503	billing_unconfigured	Usage billing is not configured on this deployment.

Create a checkout session

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