Flat / AAC hosting
AAC hosting: upload AAC audio and share a URL
Publish a finished AAC file from your browser or the CLI. Share the original export with a browser listening link where its profile and packaging are supported.
Checking your upload limits... · Public · Limits
Drop your AAC files here
or choose them from your device.
Select AAC filesWhat listeners see at your AAC link
The example is AAC-LC audio in an ADTS .aac file, displayed in Flat's audio player. Standalone AAC playback varies by browser and operating system.
AAC names the codec. Its profile and container matter too. A browser that plays AAC inside M4A may handle a standalone AAC file differently.
A single supported file opens with browser playback controls. Several files open in the explorer, where listeners can choose a recording. Public links need no Flat account. Original downloads remain available.
The exact path /audio-sample.aac serves the original audio. Use the main link for Flat's viewer or the exact file URL with your own player.
How to upload AAC audio and get a link
Prepare your recording
Check the AAC profile and file packaging produced by your encoder. The sample uses AAC-LC with ADTS framing. Keep the filename extension consistent with the exported file.
If your audience needs AAC inside an MPEG-4 container, export or remux it with an audio tool and follow the M4A guide. Flat does not repackage audio, and renaming the extension does not perform that step.
Publish from your browser or terminal
In your browserGo to uploaderDrop, publish, copy the link.
Drop your finished recordings into the uploader above, or choose them from your device. Enter your email if signed out, then choose "Publish audio".
Selected files need unique names and publish at the top level. Use the CLI for folders; the browser uploader does not accept folders or extract ZIPs.
TerminalNode.js 20+One command. Files or folders.
npx -y @getflat/cli deploy ./audio-sample.aacReplace the example path with your recording, or pass a folder path for several files. The CLI preserves relative paths and prints the published URL.
Listen before sharing
Listen to the standalone AAC in your target browsers, including mobile devices. If playback fails, keep the download available and publish a compatible export for listening.
Signed-out uploads expire after 1 hour by default. Sign in before expiry to keep them online, or sign in before publishing for no default expiry.
What you can share with AAC hosting
Encoder output reviews
Share a standalone AAC export so a colleague can inspect the exact file. Keep profile and bitrate decisions in your encoding workflow.
Device audio delivery
Provide an AAC file required by a particular player or application. Recipients download and check it on the target device.
Packaging comparisons
Publish an AAC file alongside a separately prepared M4A version. Compare playback in the browsers you need to support.
Keep a version, or keep an address.
Share this version
Every upload gets its own link. Publishing revised files creates a new link and leaves the earlier version unchanged. Use the version link when someone needs to review a specific upload.
Update files at one address
Use a named onflat.page address or your own domain. Sign in, then publish with the CLI using --domain. Publish revised files with the same domain to point that address to the new upload.
Named addresses are included on Free. Adding your own domain requires a paid plan. The browser uploader does not set up or repoint these addresses.
AAC hosting questions
Is hosting free, and what are the limits?
Yes. Signed-in Free includes 5 MiB per upload, 1 GiB of storage, and 5 GiB of monthly transfer, with no default expiry. The per-upload limit covers all files in that upload. Paid plans raise these limits.
Do readers need a Flat account?
No. Public links open without a Flat account. Anyone with the link can open the uploaded files. Password-protected links also require the visitor password.
Can I password-protect my upload?
Yes. Password protection is available on every plan. Add --password YOUR_PASSWORD to your CLI deploy command. It protects access to the upload and its files, but does not prevent someone with access from saving a copy. The browser uploader creates public uploads.
Can I replace files without changing the link?
A version link always refers to its original upload. For same-address updates, use a named address or your own domain. Publish revised files with the same --domain value in the CLI to point that address to the new upload.
What happens when an upload expires?
Flat stops serving it. An expired upload cannot be recovered. Signed-out uploads expire after 1 hour by default. For browser uploads, use the sign-in link shown after publishing. For CLI uploads, run npx -y @getflat/cli login. Complete sign-in before expiry to keep the upload online. If you chose a shorter expiry in the CLI, that deadline stays in place.
Are AAC and M4A the same file format?
No. AAC is a codec; M4A generally indicates an audio-only MPEG-4 container. A standalone AAC file commonly uses ADTS framing. AAC audio can also be stored inside M4A.
Will every AAC profile play online?
No. Support depends on the AAC profile, packaging, browser, and operating system. Check the actual file on your audience's devices. Flat does not transcode unsupported profiles.
Does hosting AAC turn it into a live stream?
No. Flat serves a finished uploaded file. It does not ingest live audio or create segmented streaming playlists.
How large can a AAC preview be?
Flat's built-in viewer previews audio files up to 5 MiB, provided the browser supports the encoding. Your hosting plan may allow larger uploads, but paid plans do not raise this preview limit. Larger recordings remain available at their original URLs for downloading or use with your own compatible player.
Can I embed my AAC recording on a website?
Use a public upload's original audio URL:
<audio controls src="https://YOUR-ADDRESS.onflat.page/audio-sample.aac"></audio>The generated Flat viewer cannot be embedded in an iframe. Your own player still relies on browser codec support and autoplay rules.
Another audio format?
Find the guide for your audio file.
Share your next AAC recording.
Publish the finished audio, check playback, and copy the link.
Publish audioFree to start · View pricing