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Open an .aup4 project without Audacity

Drop an Audacity project and listen to it, see every track and clip, and export a WAV or MP3 — on this page, on any machine. The file is read on your own device and never leaves it.

Drop your project here
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AUP4AUP3
Ready — 0 bytes uploadedFile API · Web Worker · SQLite in WebAssembly
Direct answer

Can I open an .aup4 file without Audacity 4?

Yes. An .aup4 file is a single SQLite database: the audio sits inside it as blocks of raw samples, and a compact binary-encoded document describes the tracks and clips. Waveward reads that database in your browser, rebuilds each track from its clips, and plays or exports the result — no Audacity install and no upload. Audacity 3 cannot open .aup4 because its format version is newer than 3.7 accepts; if you need the project back in Audacity 3, use the downgrade tool.

STEP 01

Drop the .aup4 or .aup3 file — it is read locally, with nothing uploaded.

STEP 02

See every track and clip on a timeline and play the mix straight away.

STEP 03

Export the stereo mix to WAV or MP3 free, for projects up to 256 MB.

STEP 04

Pro rebuilds damaged projects, downgrades .aup4 to .aup3, exports per-track stems, and exports projects larger than 256 MB.

Why it matters

Open an .aup4 project without Audacity

Audacity never saves your recording as something a player can open. It saves a project — .aup4 since Audacity 4.0, .aup3 in Audacity 3 — and until now only Audacity itself could read one. Send a project to a collaborator, open it on a Chromebook, or find it on an old drive after the app is gone, and there was no way in.

Waveward reads both formats directly in your browser, rebuilds the timeline the way Audacity draws it, and lets you play the result or export it. Opening, listening and exporting the stereo mix are free; recovery, downgrading and per-track stems are the paid step.

On a Mac? Audacity's own recovery utility only gained a macOS build in January 2026, and it is still a terminal program that asks for about four times the project's size in free space. Everything on this page runs in the browser instead, on any operating system.

The format itself

What an .aup4 file actually is

Since Audacity 3.0 a project has been one SQLite database file, and Audacity 4.0 kept that design under the new .aup4 extension. Four tables matter: `project` holds the saved project document, `autosave` holds the crash-recovery copy written after every edit, `sampleblocks` holds the audio, and `project_history` — new in Audacity 4 — keeps a few earlier saves so a damaged document can be rolled back.

The audio is stored as immutable blocks of up to about a megabyte, in 16-bit, 24-bit or 32-bit float samples. Audacity never edits a block in place: every change writes new blocks and the document points at them. That is why a project file grows so quickly, and also why the audio is usually intact even when the document is not.

The project document is XML, but stored in a compact binary encoding: a dictionary assigns a two-byte id to every element and attribute name, and the document references those ids. Waveward decodes that token stream, follows each clip to its blocks, applies the clip's offset, trims and amplitude envelope, and mixes the tracks — the same reconstruction Audacity performs when it draws the timeline.

Audacity 4 also raises the document's format version and adds clip fields Audacity 3 has never seen: clip groups, a per-clip tempo, a stretch-to-project-tempo flag, and a per-clip selection flag.

Format
One SQLite database file — the same design as .aup3
Introduced
Audacity 4.0.0, released 3 September 2026
Tables
project · autosave · sampleblocks · project_history
Audio storage
Immutable blocks up to ~1 MB; 16-bit, 24-bit or 32-bit float samples
Project document
XML in a binary token encoding with a name dictionary
Opens in Audacity 3?
No — both the database stamp and the document's format version are newer than 3.7 accepts
.aup3 → .aup4
Automatic and one-way in Audacity 4; the original .aup3 is left unchanged
Realtime effects
Not rendered here — exports are a dry mix with clip gain and envelopes applied

New to the format? What an .aup4 file is, table by table — and how it differs from .aup3.

Questions

Before you trust a recording to a website

Q. Does my recording really stay private?

Yes. The project is opened with the browser's File API and parsed in a Web Worker on your own machine. Nothing about it is sent anywhere — you can disconnect from the network after the page loads and keep working.

Q. Will the audio match what I hear in Audacity?

For an unprocessed project, yes: the same samples, clip positions, trims, volume, pan and amplitude envelopes Audacity saved are used. Realtime effects and master-track effects are not rendered, so a project whose sound depends on them should be exported from Audacity instead. The page tells you how many effects a project has as soon as it opens.

Q. My project is several gigabytes. Will it work?

Any project the browser tab can hold opens and plays; exporting one larger than 256 MB is part of Pro. There is no streaming reader: the whole project is read into the tab's memory — the file bytes plus SQLite's own copy, so roughly twice the file size — with the rendered mix on top. A project of a few gigabytes therefore needs a 64-bit browser with that much memory to spare, and one the browser cannot hold fails at the open step with a message saying so; nothing opens partially.

Q. Audacity says my project is corrupted. Can you fix it?

Often, yes. The audio blocks usually survive; what breaks is the database structure or the project document. The recovery page runs the integrity check, falls back to the autosave copy or an earlier save kept inside the file, fills gaps with silence, and rebuilds a clean project, in the browser on a Mac as well as on Windows or Linux. Audacity's own audacity-project-tools does the same job from a terminal, reads only the project and autosave documents rather than the earlier saves in project_history, and treats an .aup4 as a damaged 3.7 project because its supported version stops at 3.7.0.0.

Pricing

Simple, one-time pricing

Opening a project, seeing its tracks and playing it are free forever, at any size your browser can hold; exporting the stereo mix is free up to 256 MB. Recovery, downgrading, stems and larger exports are a one-time unlock — no subscription, no recurring fees.

Free
$0

Everything you need to hear and export a project.

  • Open .aup4 and .aup3 projects — locally, at any size the tab can hold
  • See every track and clip; play the mix in the browser
  • Export the stereo mix to WAV (16-bit or 32-bit float) or MP3, up to 256 MB
  • Read the project's facts: sample rate, tracks, clips, blocks, saved-with version
  • Run the integrity check and see the full recovery report
  • Files never leave your device
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