--- title: TTS-1 HD description: OpenAI's high-definition text-to-speech model producing higher quality audio output. image: https://developers.cloudflare.com/dev-products-preview.png --- > Documentation Index > Fetch the complete documentation index at: https://developers.cloudflare.com/ai/llms.txt > Use this file to discover all available pages before exploring further. [Skip to content](#%5Ftop) ![OpenAI logo](https://developers.cloudflare.com/_astro/openai.BI8PEEzI.svg) # TTS-1 HD Text-to-Speech • OpenAI `openai/tts-1-hd` OpenAI's high-definition text-to-speech model producing higher quality audio output. | Model Info | | | ------------------- | ----------------------------------------------------------------------------------------------------------------- | | Terms and License | [link ↗](https://openai.com/policies/) | | More information | [link ↗](https://platform.openai.com/docs/guides/text-to-speech) | | Zero data retention | Yes | | Pricing | [View pricing in the Cloudflare dashboard ↗](https://dash.cloudflare.com/?to=/:account/ai/models/openai/tts-1-hd) | ## Usage * [ TypeScript ](#tab-panel-1516) * [ cURL ](#tab-panel-1517) TypeScript ``` const response = await env.AI.run( 'openai/tts-1-hd', { response_format: 'mp3', speed: 1, text: 'Hello! Welcome to Cloudflare AI Gateway. Let me show you what we can do.', voice: 'alloy', },)console.log(response) ``` Terminal window ``` curl https://api.cloudflare.com/client/v4/accounts/$CLOUDFLARE_ACCOUNT_ID/ai/run \ --header "Authorization: Bearer $CLOUDFLARE_API_TOKEN" \ --header "Content-Type: application/json" \ --data '{ "model": "openai/tts-1-hd", "input": { "response_format": "mp3", "speed": 1, "text": "Hello! Welcome to Cloudflare AI Gateway. Let me show you what we can do.", "voice": "alloy" }}' ``` * [ Output ](#tab-panel-1512) * [ Raw response ](#tab-panel-1513) ``` { "gatewayMetadata": { "keySource": "Unified" }, "result": { "audio": "https://pub-04a6d208d361438ea01b797e6973bd19.r2.dev/catalog/openai__tts-1-hd/simple-speech.mp3" }, "state": "Completed"} ``` ## Examples **Storytelling** — HD narration with the Fable voice * [ TypeScript ](#tab-panel-1520) * [ cURL ](#tab-panel-1521) TypeScript ``` const response = await env.AI.run( 'openai/tts-1-hd', { response_format: 'mp3', speed: 0.9, text: 'Once upon a time, in a kingdom beyond the clouds, there lived a young inventor who dreamed of building machines that could think.', voice: 'fable', },)console.log(response) ``` Terminal window ``` curl https://api.cloudflare.com/client/v4/accounts/$CLOUDFLARE_ACCOUNT_ID/ai/run \ --header "Authorization: Bearer $CLOUDFLARE_API_TOKEN" \ --header "Content-Type: application/json" \ --data '{ "model": "openai/tts-1-hd", "input": { "response_format": "mp3", "speed": 0.9, "text": "Once upon a time, in a kingdom beyond the clouds, there lived a young inventor who dreamed of building machines that could think.", "voice": "fable" }}' ``` * [ Output ](#tab-panel-1514) * [ Raw response ](#tab-panel-1515) ``` { "gatewayMetadata": { "keySource": "Unified" }, "result": { "audio": "https://pub-04a6d208d361438ea01b797e6973bd19.r2.dev/catalog/openai__tts-1-hd/storytelling.mp3" }, "state": "Completed"} ``` **Podcast Style** — Conversational podcast narration * [ TypeScript ](#tab-panel-1524) * [ cURL ](#tab-panel-1525) TypeScript ``` const response = await env.AI.run( 'openai/tts-1-hd', { response_format: 'mp3', speed: 1, text: "So here's the thing about large language models — they're not actually thinking. They're predicting the next token based on patterns in their training data. But the results can be surprisingly coherent.", voice: 'echo', },)console.log(response) ``` Terminal window ``` curl https://api.cloudflare.com/client/v4/accounts/$CLOUDFLARE_ACCOUNT_ID/ai/run \ --header "Authorization: Bearer $CLOUDFLARE_API_TOKEN" \ --header "Content-Type: application/json" \ --data '{ "model": "openai/tts-1-hd", "input": { "response_format": "mp3", "speed": 1, "text": "So here'\''s the thing about large language models — they'\''re not actually thinking. They'\''re predicting the next token based on patterns in their training data. But the results can be surprisingly coherent.", "voice": "echo" }}' ``` * [ Output ](#tab-panel-1518) * [ Raw response ](#tab-panel-1519) ``` { "gatewayMetadata": { "keySource": "Unified" }, "result": { "audio": "https://pub-04a6d208d361438ea01b797e6973bd19.r2.dev/catalog/openai__tts-1-hd/podcast-style.mp3" }, "state": "Completed"} ``` **Shimmer Voice** — Bright and expressive voice * [ TypeScript ](#tab-panel-1526) * [ cURL ](#tab-panel-1527) TypeScript ``` const response = await env.AI.run( 'openai/tts-1-hd', { response_format: 'mp3', speed: 1, text: 'Breaking news: scientists have discovered a new species of deep-sea fish that produces its own light using bioluminescence.', voice: 'shimmer', },)console.log(response) ``` Terminal window ``` curl https://api.cloudflare.com/client/v4/accounts/$CLOUDFLARE_ACCOUNT_ID/ai/run \ --header "Authorization: Bearer $CLOUDFLARE_API_TOKEN" \ --header "Content-Type: application/json" \ --data '{ "model": "openai/tts-1-hd", "input": { "response_format": "mp3", "speed": 1, "text": "Breaking news: scientists have discovered a new species of deep-sea fish that produces its own light using bioluminescence.", "voice": "shimmer" }}' ``` * [ Output ](#tab-panel-1522) * [ Raw response ](#tab-panel-1523) ``` { "gatewayMetadata": { "keySource": "Unified" }, "result": { "audio": "https://pub-04a6d208d361438ea01b797e6973bd19.r2.dev/catalog/openai__tts-1-hd/shimmer-voice.mp3" }, "state": "Completed"} ``` ## Parameters * [ Input ](#tab-panel-1528) * [ Output ](#tab-panel-1529) text `string`requiredmaxLength: 4096The text to generate audio for. Maximum length is 4096 characters. voice `string`requireddefault: alloyenum: alloy, echo, fable, onyx, nova, shimmerThe voice to use when generating the audio. Defaults to alloy. response\_format `string`requireddefault: mp3enum: mp3, opus, wav, aac, flacThe output format for the audio. Supported formats are mp3, opus, wav, aac and flac. speed `number`requireddefault: 1minimum: 0.25maximum: 4The speed of the generated audio. Select a value from 0.25 to 4.0\. 1.0 is the default. audio `string`URL to the generated audio file ## API Schemas (Raw) Input [ ](https://developers.cloudflare.com/ai/models/openai/tts-1-hd/schema-input.json "Open") [ ](https://developers.cloudflare.com/ai/models/openai/tts-1-hd/schema-input.json "Download") Output [ ](https://developers.cloudflare.com/ai/models/openai/tts-1-hd/schema-output.json "Open") [ ](https://developers.cloudflare.com/ai/models/openai/tts-1-hd/schema-output.json "Download") ```json {"@context":"https://schema.org","@type":"TechArticle","@id":"https://developers.cloudflare.com/ai/models/openai/tts-1-hd/#page","headline":"TTS-1 HD (OpenAI) · Cloudflare AI docs · Cloudflare AI docs","description":"OpenAI's high-definition text-to-speech model producing higher quality audio output.","url":"https://developers.cloudflare.com/ai/models/openai/tts-1-hd/","inLanguage":"en","image":"https://developers.cloudflare.com/dev-products-preview.png","publisher":{"@type":"Organization","name":"Cloudflare","url":"https://www.cloudflare.com/"},"isPartOf":{"@type":"WebSite","@id":"https://developers.cloudflare.com/#website","name":"Cloudflare Docs","url":"https://developers.cloudflare.com/"}} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"/directory/","name":"Directory"}},{"@type":"ListItem","position":2,"item":{"@id":"/ai/","name":"AI"}},{"@type":"ListItem","position":3,"item":{"@id":"/ai/models/","name":"Models"}}]} ```