OpenAI model

TTS 1 API

openai/tts-1 converts text to speech and is billed by input characters: $0.15 per 10,000 characters. Token prices do not apply to this id, and no context window is published. The hd sibling, openai/tts-1-hd, is listed at $0.30 per 10k characters — double the price on the same unit.

Read quickstartEstimate cost
OpenAIPlatform curatedCatalog
Speech price$0.15 / 10k chars
BillingPer 10k input characters
Context length— tokens
Max output8.2k tokens

What is TTS 1 API in NextModel?

openai/tts-1 converts text to speech and is billed by input characters: $0.15 per 10,000 characters. Token prices do not apply to this id, and no context window is published. The hd sibling, openai/tts-1-hd, is listed at $0.30 per 10k characters — double the price on the same unit.

TTS 1 via NextModel: context unpublished; $0.15 / 10k chars in / — out per 1M tokens.

Best use cases

  • Text-to-speech where $0.15 per 10k input characters fits the budget.
  • Voice workloads that only need the standard tier rather than the $0.30-per-10k hd id.
  • Pipelines already using an OpenAI-compatible speech endpoint.

When not to use

  • You need the higher-fidelity tier: openai/tts-1-hd is $0.30 per 10k characters.
  • You expect per-token billing — this id is billed per input characters.
  • You need a published context window: none is published for this id.

OpenAI-compatible code example

request.sh
curl https://api.nextmodel.app/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $NEXTMODEL_API_KEY" \
  -d '{"model":"openai/tts-1","messages":[{"role":"user","content":"Reply with OK."}]}'

Switching models only changes the model field.

Try it in the playground

Speech models use the chat shape for now - see the audio guide.

Similar alternatives

OpenAICatalog

GPT-5 Codex

GPT-5 Codex via NextModel: 400k-token context; $1.25 / 1M tokens in / $10 / 1M tokens out per 1M tokens. Capabilities: streaming.

$1.25 / 1M tokensInput$10 / 1M tokensOutput400kContext
Best forGeneral chat via OpenAI, API workloads
Streaming
Platform curatedCurated and maintained in the NextModel catalog
View details
OpenAICatalog

Text Embedding 3 Large

Text Embedding 3 Large via NextModel: context unpublished; $0.13 / 1M tokens in / $0 / 1M tokens out per 1M tokens. Capabilities: streaming.

$0.13 / 1M tokensInput—Output—Context
Best forGeneral chat via OpenAI, API workloads
Streaming
Platform curatedCurated and maintained in the NextModel catalog
View details
OpenAICatalog

Text Embedding 3 Small

Text Embedding 3 Small via NextModel: context unpublished; $0.02 / 1M tokens in / $0 / 1M tokens out per 1M tokens. Capabilities: streaming.

$0.02 / 1M tokensInput—Output—Context
Best forGeneral chat via OpenAI, API workloads
Streaming
Platform curatedCurated and maintained in the NextModel catalog
View details

Compare TTS 1

TTS 1 vs GPT-5 CodexTTS 1 vs Text Embedding 3 LargeTTS 1 vs Text Embedding 3 SmallTTS 1 vs TTS 1 HDTTS 1 vs Whisper Large V3 Turbo

Reading

Articles that explain TTS 1

FAQ

TTS 1 API questions

What model id do I send for TTS 1?

Send openai/tts-1 to https://api.nextmodel.app/v1 with your OpenAI SDK. If that id is missing from /v1/models, the page is stale.

How is TTS 1 billed?

$0.15 per 10,000 input characters. It is not billed per token.

TTS 1 or TTS 1 HD?

tts-1 is $0.15 per 10k input characters; tts-1-hd is $0.30. Same unit, double the price — pick by output fidelity needs.

Start now

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