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

# Audio

> Two audio models on two endpoints. Speech-to-text and audio-scene Q&A — pay per minute.

Kyma serves two audio models behind two synchronous endpoints, billed per minute of processed audio:

* **Transcription** — what was said. OpenAI Whisper API compatible.
* **Audio understanding** — everything else. Tone, music, SFX, language, speaker emotion. Custom Kyma endpoint.

Both are sync (no polling), use `multipart/form-data` upload, and accept `mp3` / `wav` / `m4a` / `ogg` / `webm` / `flac` up to 25 MB (\~30 min of mono 16kHz mp3).

## Pick a model

| Model                                                  | Endpoint                   | Best for                            | Cost / min | Min billable |
| ------------------------------------------------------ | -------------------------- | ----------------------------------- | :--------: | :----------: |
| [`whisper-v3-turbo`](/models/whisper-v3-turbo)         | `/v1/audio/transcriptions` | Transcripts, captions, voice agents |  \$0.0009  |     1 min    |
| [`gemini-3-flash-audio`](/models/gemini-3-flash-audio) | `/v1/audio/understand`     | Tone, music, SFX, mood, language    | \$0.000648 |     1 min    |

Both bill in 1-minute increments, rounded up. A 1-hour file: $0.054 transcribe + $0.039 understand = **\$0.093 total**.

## Aliases

Use these in the `model` field instead of pinning a specific SKU. Aliases auto-track the current best model — when a faster Whisper or a stronger Gemini lands, you don't change your code.

| Alias              | Resolves to            |
| ------------------ | ---------------------- |
| `transcribe`       | `whisper-v3-turbo`     |
| `audio-understand` | `gemini-3-flash-audio` |

## whisper-v3-turbo

**Speech-to-text.** 228x realtime inference. Returns transcripts with per-segment timestamps and detected language. OpenAI Whisper API compatible.

```bash theme={null}
curl -X POST https://kymaapi.com/v1/audio/transcriptions \
  -H "Authorization: Bearer $KYMA_API_KEY" \
  -F "file=@meeting.mp3" \
  -F "model=transcribe"
```

* **Cost**: \$0.0009 / min
* **Best for**: meeting notes, voice agent input, podcast captions
* **Output**: text + segments with timestamps

## gemini-3-flash-audio

**Audio understanding.** Hears tone, music, SFX, language, speaker emotion — the things a transcript drops on the floor. Ask a free-form question, get a natural-language answer.

```bash theme={null}
curl -X POST https://kymaapi.com/v1/audio/understand \
  -H "Authorization: Bearer $KYMA_API_KEY" \
  -F "file=@scene.mp3" \
  -F "model=audio-understand" \
  -F "question=Describe the mood and any background music."
```

* **Cost**: \$0.000648 / min
* **Best for**: mood/tone analysis, music recognition, scene understanding
* **Output**: free-form answer to your question

## Use them together — the decomposition trick

A video is just frames + audio. You almost never need a multimodal LLM on the full video — each piece has a fast, near-free tool:

```text theme={null}
URL ──▶ yt-dlp ──▶ video.mp4 ──┬──▶ ffmpeg ──▶ frames/*.jpg
                                │
                                └──▶ ffmpeg ──▶ audio.mp3 ──┬──▶ /v1/audio/transcriptions
                                                            │     (the words)
                                                            │
                                                            └──▶ /v1/audio/understand
                                                                  (everything else)
```

[`watch-cli`](https://github.com/sonpiaz/watch-cli) is an open-source orchestrator built on exactly this pattern — install it, point at any social video URL, and your agent gets back frames + transcript + audio scene.

| Approach                     | Cost / 1-hour video |   Time   |
| ---------------------------- | :-----------------: | :------: |
| Multimodal LLM on full video |        \~\$5        |  30-60s  |
| Decompose with Kyma audio    |      \< \$0.10      | \~10-15s |

The savings compound when an agent watches dozens of videos in a session.

## See also

* [`POST /v1/audio/transcriptions`](/api-reference/audio-transcriptions) - endpoint reference for transcribe
* [`POST /v1/audio/understand`](/api-reference/audio-understand) - endpoint reference for audio Q\&A
* [Model aliases](/guides/model-aliases) - why aliases stay stable when SKUs change