# MP3 to MP4: turn audio into a waveform video

Make an MP4 audio visualizer or audiogram with a reactive waveform, title and cover.

## How it works

1. Add your MP3, WAV, M4A or other recording, then pick a visualizer look and frame shape.
2. Press Make video to open the editor on Visuals, where the waveform reacts to your sound.
3. Add cover art, a background or titles, then export your MP4 video.

## From audio file to waveform video

Video platforms such as YouTube, TikTok, Instagram, LinkedIn and X reject audio-only MP3 files, and renaming an MP3 to MP4 without a video track still fails on upload. Audo turns an uploaded MP3, WAV, M4A or FLAC recording into an H.264 MP4 video with a live waveform that moves with the voice or music, a title, a progress bar and optional cover art.

Whether you need a podcast audiogram for social feeds or an audio to video visualizer for a song or beat on YouTube, the preview on the canvas is drawn by the same renderer that exports the MP4. Start from six presets—Podcast square, Shorts, Minimal line, Sunset, Ring and Bold—and adjust the waveform style, colours, cover and frame shape before exporting.

Tool: Audio to video (`audio_to_video`). Price: 2 credits a minute — $0.02/min ($1.20/hr), with no subscription — of input for whole files, charged only when a job succeeds.

## Free API

```bash
curl -F file=@podcast.mp3 -F preset=podcast_square https://audo.ai/api/try/audio-to-video -D response.headers -o response.body
```

Read response.headers and response.body before naming media. Handle 202, 200 JSON and errors with the complete response client at https://audo.ai/docs/api?utm_source=markdown&utm_medium=agent#responses.

Free for the first 2 minutes of each file, 3 times a day per person, with no key or account. Uploads up to 10 GB, 2 at once from one address. The response is the result itself; a job that runs longer than about 30 seconds returns 202 with a link to check on it. With an API key (`-H "Authorization: Bearer $AUDO_API_KEY"`), omitting free runs the whole file with credits if the balance covers it, otherwise the free portion if quota remains. Set free=true to prohibit spending; for paid whole files use free=false with an approved positive max_credits. A free result cut short comes with finishUrl (and the Audo-Finish-Url header when the response is the file itself): give it to the person, who pays there (from $5, no sign-up), and the whole file runs; keep checking the status link, whose finishedBy names the whole-file job and its own status link. Details: https://audo.ai/docs/api.md

## Options

Form fields with the same names as the MCP tool's inputs:

- `preset`: A built-in look; list_audiogram_presets returns complete documents. Explicit audiogram replaces it.
- `audiogram`: Complete AudiogramDocument v1. Positions and sizes are normalized. Includes optional already timed caption document.

## Languages

Any language: it works on the sound, not the words.

## From an assistant (MCP)

Add https://audo.ai/mcp and sign in (setup for each assistant: https://audo.ai/setup.md). The tool is `audio_to_video`:

> Turns audio or a video's sound into an MP4 audiogram with a reactive waveform. Choose a preset with list_audiogram_presets or supply AudiogramDocument v1: ratio, dimensions, background, bars/line/mirror/circle/dots, colors, cover art, title, subtitle, progress and optional timed captions. cover_file_id supplies an image. It costs 2 credits a minute of audio, charged only if the job succeeds. Free for the first 2 minutes, 3 times a day. Returns MP4 and the document JSON with download links, or job_id for get_job if it takes longer.

Example: "Use Audo to turn podcast.mp3 into a square audiogram video."

## Questions

**How do I convert MP3 to MP4, and what will the video look like?** Add your MP3 above, pick a look and frame shape, and press Make video to open the editor. Because an MP3 has no picture of its own, Audo creates an MP4 waveform video that reacts to your sound, with a title, optional cover art and a progress bar. Every export includes a moving waveform rather than a blank black screen or a plain static image.

**Is this an audio visualizer or an audiogram maker?** It works as both. Podcasters call a spoken clip with a waveform, title and cover art an audiogram; musicians and YouTube creators call a sound-reactive video an audio visualizer. As an audio visualizer and audiogram maker, Audo offers five 2D waveform styles—bars, line, mirrored bars, a circular ring and dots—with custom colours, thickness, gap, sensitivity and smoothing. It draws clean 2D soundwaves rather than 3D particle effects.

**Can I make a vertical audio visualizer or YouTube video?** Yes. Choose Square (1:1), Vertical (9:16), Wide (16:9) or Portrait (4:5) on the page or under Frame in the editor. The Shorts look starts with a tall 9:16 frame for TikTok, Reels and YouTube Shorts, while Wide (16:9) fits full-length YouTube uploads and Square (1:1) fits podcast feeds.

**Can I use my own cover art, background image and titles?** Yes. Under Visuals in the editor, upload a PNG, JPEG or WebP as a square or rounded cover box, as a blurred background image, or both, or pick a solid colour or two-colour gradient. Switch to Text to edit the title and subtitle font, size, colour and placement on the canvas. Every layout keeps the moving waveform; to put words or a logo onto a video that already has its own footage, use Add text to video.

**Does the visualizer change my audio quality?** No. The waveform follows the loudness of your recording without filtering, shortening or remixing the sound, and YouTube, TikTok and Instagram accept the exported H.264 MP4 with AAC audio directly. In the editor you can also turn on Remove noise, Audio enhancer, captions or trims before you export if the recording needs cleanup.

**Is MP3 to MP4 free?** Audo renders the first two minutes free, three times a day, without a watermark or sign-up. A free result ends at that limit even when the source is longer. The whole recording costs $0.02 a minute ($1.20 an hour), charged only on success. No subscription. See pricing. You can also start from WAV, M4A, FLAC and other supported audio formats.

## More

- Every tool: https://audo.ai/llms.txt
- OpenAPI: https://audo.ai/api/openapi.json
- This page for people: https://audo.ai/mp3-to-mp4?utm_source=markdown&utm_medium=agent