Credits and packs

New eligible accounts receive the current introductory settings once per service. Launch defaults are 100 STT credits (2,000 seconds) and 100 TTS credits (10,000 input characters). Existing awards do not change when settings change.

One STT credit covers 20 input seconds. Each request rounds source duration up to the next second once, then divides by 20 for display. A 14.12-second recording uses 15 seconds, or 0.75 credits. Stereo channels and internal processing do not multiply the charge. STT costs $0.0025/minute.

One TTS credit covers 100 input Unicode code points, including spaces, punctuation and combining marks. A 29-character request uses 0.29 credits; 2,000 characters uses 20. Generated duration is informational. TTS costs $0.01/1,000 input characters.

Balances are independent and cannot cover each other’s shortfalls. Credit reads show allocated, used, pending and available credit. Negative credit after a refund remains visible. An account-wide payment hold can block both operations.

Prepaid packs

Choose a $5, $20 or $100 pack for STT or TTS. Each purchase adds prepaid credit to the selected service. The $20 packs include 10% bonus credit and the $100 packs 20%, so the larger packs cost less per credit than the rates above. Packs are one-time purchases; there is no subscription or automatic recharge.

The two allowances are alternatives: an STT pack does not include TTS credit, and a TTS pack does not include STT credit.

Purchase packs from your API account. A completed purchase replenishes only its selected service after verified payment; a saved card or checkout redirect does not award credit.

How failed, retried and interrupted requests are charged is described under retries and failures.