Flat / M4A hosting
M4A hosting: upload voice recordings and share a link
Turn an exported M4A recording into a shareable URL. Publish from your browser or the CLI, then send a listening link and access to the original file.
Checking your upload limits... · Public · Limits
Drop your M4A files here
or choose them from your device.
Select M4A filesWhat listeners see at your M4A link
The screenshot shows an M4A file containing AAC audio in Flat's viewer. Compatible browsers provide playback, seeking, and volume controls.
M4A usually names audio in an MPEG-4 container. It can contain lossy AAC or lossless ALAC; the extension alone does not tell you which one it uses.
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.m4a serves the original audio. Use the main link for Flat's viewer or the exact file URL with your own player.
How to upload M4A audio and get a link
Prepare your recording
Export your recording to an M4A file on your device before uploading. Check the export's codec and play it outside the recording app so you know it is a complete file.
An AAC-encoded M4A and a standalone
.aacfile package audio differently. See AAC hosting for that workflow. Renaming a file does not change its container or codec.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.m4aReplace 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
Play the published M4A on the devices your listeners use. If you exported ALAC, check browser support rather than assuming it will behave like an AAC recording.
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 M4A hosting
Exported voice memos
Share a voice memo after saving its M4A file from your recording app. The listener gets a URL rather than an app-specific attachment.
Interview excerpts
Publish a short edited excerpt for review. Flat hosts the finished file; editing and transcription stay in your existing tools.
Audio export delivery
Send the exact M4A a client or application needs. The original download keeps its existing container, codec, and metadata.
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.
M4A 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.
Can I upload a voice memo as M4A?
Yes. First export or save the recording as a file from your app, then upload it above or use the CLI. Flat does not connect directly to your voice-memo library.
Is every M4A file lossless?
No. AAC is lossy; ALAC is lossless. Both can use the M4A extension. Flat keeps whichever encoding you upload and does not improve its source quality.
Why does one M4A play while another fails?
The files may contain different codecs or profiles. Playback also depends on browser and operating-system support. Check the export settings or download the original for a compatible player.
How large can a M4A 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 M4A recording on a website?
Use a public upload's original audio URL:
<audio controls src="https://YOUR-ADDRESS.onflat.page/audio-sample.m4a"></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 M4A recording.
Publish the finished audio, check playback, and copy the link.
Publish audioFree to start · View pricing