--- description: Record separate audio tracks for selected RealtimeKit participants and download per-participant WebM files. title: Track recording image: https://developers.cloudflare.com/og-docs.png --- [Skip to content](#main-content) > Documentation Index > Fetch the complete documentation index at: https://developers.cloudflare.com/realtime/llms.txt > Use this file to discover all available pages before exploring further. # Track recording Last updated Aug 24, 2026|Copy as Markdown|[View as Markdown](https://docs-durable-objects-instance-replaced-errors.previews.developers.cloudflare.com/realtime/realtimekit/recording-guide/track-recording/index.md)|[Agent setup](https://docs-durable-objects-instance-replaced-errors.previews.developers.cloudflare.com/agent-setup/) Track recording lets you record participant audio as separate WebM files instead of one composite meeting recording. Use it when you need speaker-level control over what you store, process, or review. With track recording, you can record specific participant tracks by passing `user_ids`, which is useful for content-sensitive or regulated workflows where recording every participant is unnecessary. If you do not provide `user_ids`, RealtimeKit will record all participant audio tracks as separate WebM files by default. To pass `user_ids` for specific participant track recording, use the following minimum SDK versions: * Web Core: `@cloudflare/realtimekit` version `1.4.0` or later * Web UI Kit: `@cloudflare/realtimekit-ui`, `@cloudflare/realtimekit-react-ui`, or `@cloudflare/realtimekit-angular-ui` version `1.1.2` or later * Android Core or iOS Core: version `2.0.0` or later * Android UI Kit or iOS UI Kit: version `1.1.0` or later Track recording creates one file per recorded participant. Note Track recording currently supports audio tracks only. Video track recording is in development. ## Availability and limits Track recording has the following requirements and limits: | Limit | Description | | --------------------- | ---------------------------------------------------------------------------- | | Active meeting | The meeting must have an active live session. | | Media kind | Only audio layers are recorded. | | Participant selection | Pass up to 100 values in user\_ids. | | Storage | Files are uploaded to RealtimeKit's managed R2 bucket with zero-egress fees. | | File retention | RealtimeKit bucket download URLs expire after seven days. | ## Start track recording ### Record specific participants To record separate audio tracks for specific participants, call [POST /recordings/track](https://docs-durable-objects-instance-replaced-errors.previews.developers.cloudflare.com/api/resources/realtime%5Fkit/subresources/recordings/methods/start%5Ftrack%5Frecording/) with the meeting ID and the participant `user_ids`. ```bash curl --request POST \ --url https://api.cloudflare.com/client/v4/accounts//realtime/kit//recordings/track \ --header 'Authorization: Bearer ' \ --header 'Content-Type: application/json' \ --data '{ "meeting_id": "97440c6a-140b-40a9-9499-b23fd7a3868a", "user_ids": ["user-123", "user-456"] }' ``` RealtimeKit records current and future participants whose `user_id` matches the allowlist. Participants whose `user_id` is not listed are not recorded. ### Record all participants as separate tracks Omit `user_ids` to record separate audio tracks for all participants in the live meeting. RealtimeKit creates one WebM file for each recorded participant. ```bash curl --request POST \ --url https://api.cloudflare.com/client/v4/accounts//realtime/kit//recordings/track \ --header 'Authorization: Bearer ' \ --header 'Content-Type: application/json' \ --data '{ "meeting_id": "97440c6a-140b-40a9-9499-b23fd7a3868a" }' ``` The response includes a recording ID. Use this ID to stop or fetch the recording. ```json { "success": true, "data": { "recording": { "id": "fff40c6a-140b-40a9-9499-b23fd7a3868a", "meeting_id": "97440c6a-140b-40a9-9499-b23fd7a3868a", "status": "INVOKED", "type": "TRACK", "output_file_name": "{{file_name_prefix}}_{{user_id}}_{{peer_id}}_{{stream_kind}}_{{media_kind}}_{{date_time}}.webm" } } } ``` ## Customize file names with prefixes Use `layers.default.file_name_prefix` to prefix every generated track recording file. ```json { "meeting_id": "97440c6a-140b-40a9-9499-b23fd7a3868a", "layers": { "default": { "media_kind": "audio", "file_name_prefix": "speaker" } } } ``` If you omit `layers`, RealtimeKit uses `default` as the file name prefix. ## Stop track recording Use the [recording update endpoint](https://docs-durable-objects-instance-replaced-errors.previews.developers.cloudflare.com/api/resources/realtime%5Fkit/subresources/recordings/methods/pause%5Fresume%5Fstop%5Frecording/) to stop a track recording. ```bash curl --request PUT \ --url https://api.cloudflare.com/client/v4/accounts//realtime/kit//recordings/ \ --header 'Authorization: Bearer ' \ --header 'Content-Type: application/json' \ --data '{ "action": "stop" }' ``` Track recording also stops when the meeting session ends. After track recording stops, RealtimeKit uploads the per-participant WebM files and moves the recording to `UPLOADED`. ## Download track files Track recording uses the same recording status lifecycle as composite recording. To monitor status, refer to [Monitor Recording Status](https://docs-durable-objects-instance-replaced-errors.previews.developers.cloudflare.com/realtime/realtimekit/recording-guide/monitor-status/). When the recording reaches `UPLOADED`, fetch the recording details or listen for the `recording.statusUpdate` webhook. For track recordings, `download_url` contains per-participant WebM file URLs grouped by layer. ```json { "download_url": [ { "layer_name": "default", "download_urls": { "speaker_user-123_peer-456_peer_audio_1760000000000.webm": { "download_url": "https://example.com/presigned-url" } } } ] } ``` File names use this format: ```txt {{file_name_prefix}}_{{user_id}}_{{peer_id}}_{{stream_kind}}_{{media_kind}}_{{date_time}}.webm ``` The `date_time` value is the Unix timestamp in milliseconds when the file was generated. Was this helpful? YesNo ## On this page [![](https://docs-durable-objects-instance-replaced-errors.previews.developers.cloudflare.com/_astro/logo.te5VL_aD.svg)Docs](https://docs-durable-objects-instance-replaced-errors.previews.developers.cloudflare.com/) ```json {"@context":"https://schema.org","@type":"TechArticle","@id":"https://developers.cloudflare.com/realtime/realtimekit/recording-guide/track-recording/#page","headline":"Track recording ยท Cloudflare Realtime docs","description":"Record separate audio tracks for selected RealtimeKit participants and download per-participant WebM files.","url":"https://developers.cloudflare.com/realtime/realtimekit/recording-guide/track-recording/","inLanguage":"en","image":"https://developers.cloudflare.com/og-docs.png","dateModified":"2026-08-24","publisher":{"@type":"Organization","name":"Cloudflare","description":"One platform for your apps, agents, and workforce. 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