> ## Documentation Index
> Fetch the complete documentation index at: https://docs.supertoneapi.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Frequently Asked Questions

> We've compiled frequently asked questions and their answers during API usage.

We've organized the most frequently asked questions by topic, from those first using the API to users who have integrated cloned voices.

## 1. Get Started with API

<Accordion title="Where can I get an API Key?">
  You can get it immediately by signing up for the service in the [console](https://console.supertoneapi.com). You can use up to 3 Keys per account, and revocation and reissuance are possible in case of leakage.
</Accordion>

<Accordion title="How do I integrate the API?">
  When making HTTP requests, put the issued Key in the `x-sup-api-key` header. For detailed integration methods, please refer to [Quick Start](/en/user-guide/quickstart).
</Accordion>

<Accordion title="Do I need to use a different account from Play?">
  No. Play and API operate on the same account basis.
</Accordion>

## 2. Voice & API Calls

<Accordion title="Where can I check available voice IDs?">
  Voice IDs can be checked through the following three methods:

  1. Copy from the voice library in Supertone Play
  2. Call GET /v1/voices endpoint for complete inquiry
  3. Call GET /v1/voices/search endpoint for conditional search
     For more details, please check the [Voice Selection Guide](/en/user-guide/voice-selection).
</Accordion>

<Accordion title="Can I use cloned voices in the API?">
  Yes. Cloned voices created in Play can also be called in the API with the same account. Cloned voice creation is only possible in Play.
</Accordion>

<Accordion title="How can I find the ID of a cloned voice?">
  By searching with `GET /v1/voices/search?name=My Voice`, you can filter and check only cloned voices created within your account.
  For more details, please check the [Voice Selection Guide](/en/user-guide/voice-selection).
</Accordion>

<Accordion title="Can I make calls just knowing the voice ID?">
  No. In addition to `voice_id`, the `language`, `style`, and `model` combination must match exactly for voice to be generated normally.
</Accordion>

<Accordion title="What combinations are possible for each voice?">
  Through the `samples` field, you can check supported language/style/model combinations and sample audio for each voice.
  For more details, please check the [Voice Selection Guide](/en/user-guide/voice-selection).
</Accordion>

<Accordion title="Is the style parameter required?">
  No. Style is optional, and the system's default style is automatically applied if not provided.
</Accordion>

<Accordion title="Can I adjust voice speed or pitch?">
  You can adjust `pitch_shift`, `pitch_variance`, and `speed` through `voice_settings`.
</Accordion>

<Accordion title="What is the Predict Duration API for?">
  It's a feature that predicts the speech length of input text. **Credits are not deducted**.
</Accordion>

## 3. Credit & Pricing

<Accordion title="What is the API pricing plan?">
  It uses the same credit system as Play. Please check available plans on the [Play subscription page](https://play.supertone.ai/subscription).
</Accordion>

<Accordion title="How can I check my credit balance?">
  You can check through the following two methods:

  * Call `GET /v1/credits` API
  * Check console or Play dashboard
</Accordion>

<Accordion title="Are credits only deducted from the API?">
  No. Play and API share the same credits.
</Accordion>

<Accordion title="Can I use voices created in Play in the API?">
  Yes. Cloned voices created within the same account can be called in the API without additional settings.
</Accordion>

## 4. Errors & Troubleshooting

<Accordion title="What are the most common errors when making calls?">
  * 401: API Key error
  * 402: Insufficient credits
  * 403: Unauthorized voice call
  * 400: Parameter error, text overflow, etc.
  * 429: Call limit exceeded
    For more details, please check the [Error Handling](/en/user-guide/handling-errors) guide.
</Accordion>

<Accordion title="Where can I check error codes?">
  You can check them in the [Error Handling](/en/user-guide/handling-errors) guide.
</Accordion>

<Accordion title="My calls keep failing.">
  Please refer to the [Error Handling](/en/user-guide/handling-errors) guide and check the following:

  * Verify that x-sup-api-key is included in headers
  * Check if Content-Type: application/json is missing
  * Verify that voice\_id has been replaced with actual value
    If problems persist, please contact through the [customer support](https://support.supertone.ai/hc/en-us/categories/10267196754959-Play?_gl=1*wccieo*_gcl_au*NDgxOTUwMjcwLjE3NDc4MjQ4NDE.) page.
</Accordion>

<Accordion title="What are the call frequency limits?">
  We recommend 20 calls or fewer per minute by default. For higher traffic needs, separate inquiry is required.

  > 🏢 [Enterprise Inquiry](https://docs.google.com/forms/d/1YexQpjpK0ZEou12blTytkZLqvrV-Uv95GbhxoOQ54R8/edit)
</Accordion>

## 5. Operational Policy & Support

<Accordion title="Can anyone use the API?">
  Yes. You can use it immediately after signing up for the console and charging credits, with no separate approval required.
</Accordion>

<Accordion title="Is there an enterprise plan?">
  Yes. For team-level usage, user account separation, call limit expansion, and other special conditions, please contact through support.

  > 🏢 [Enterprise Inquiry](https://docs.google.com/forms/d/1YexQpjpK0ZEou12blTytkZLqvrV-Uv95GbhxoOQ54R8/edit)
</Accordion>

<Accordion title="Where do I contact if problems aren't resolved?">
  Please leave a 1:1 inquiry through the [customer support](https://support.supertone.ai/hc/en-us/categories/10267196754959-Play?_gl=1*9ehgt*_gcl_au*NDgxOTUwMjcwLjE3NDc4MjQ4NDE.) page, and we'll respond quickly.
</Accordion>