OpenAnyFile
Works
Viewing, inspecting and verifying. You get the flattened composite preview stored inside the file, plus canvas size and layer count. File details, exact byte size and the detected signature are always shown.
How to open a .psb file
You have a PSB file and nothing on your machine will touch it. Here is what the format actually is, and how to read one in about four seconds without installing anything.
What is a .psb file?
Photoshop Large Document is a design file format developed by Adobe, first appearing in 2003. It is normally produced by Adobe Photoshop.
Same structure as PSD with 64-bit offsets, raising limits to 300,000 px and 4 exabytes. Almost nothing outside Adobe reads it.
| Full name | Photoshop Large Document |
|---|---|
| File category | Design files |
| MIME type | image/vnd.adobe.photoshop |
| Magic bytes (file signature) | 38 42 50 53 (8BPS) |
| Developer | Adobe |
| Introduced | 2003 |
| Usually created by | Adobe Photoshop |
| OpenAnyFile engine | PSD composite reader |
| Opens without upload | Yes — parsed locally in your browser |
Open a .psb file in your browser
OpenAnyFile routes .psb to its PSD composite reader, which reads the flattened composite preview stored inside the file, plus canvas size and layer count.
- Open the OpenAnyFile opener in this browser — nothing to download or sign up for.
- Drag your .psb file onto the drop zone, click to browse for it, or paste it with Ctrl+V.
- The extension is detected and the file is handed to the PSD composite reader.
- Your PSB opens on its own viewer page: the flattened composite preview stored inside the file, plus canvas size and layer count.
- Use fullscreen for a closer look, or download the file back out unchanged. Works the same on Windows, macOS, Linux, Android and iOS, because it is just a web page.
What you can and cannot do with it here
Does not work
Full-fidelity rendering. Only the flattened composite is available, not individual layers.
Local-only by design, not by promise
Plenty of sites promise they delete your uploads. OpenAnyFile avoids the promise by avoiding the upload. When you drop a .psb file in, the browser grants the page temporary read access to those bytes and nothing more — the page has no path to send them anywhere. You can verify it in seconds: open DevTools, switch to the network tab, and open a file. The request list stays empty.
Frequently asked questions about PSB files
Can I open a .psb file without installing Photoshop?
Yes. OpenAnyFile's PSD composite reader runs in your browser, so you can read a PSB file with nothing installed. You get the flattened composite preview stored inside the file, plus canvas size and layer count. It will not replace the original application for editing, but it answers 'what is in this file' in seconds.
How can I check a file really is a PSB file?
Look at the first bytes rather than the extension. A genuine PSB begins with 38 42 50 53 (8BPS). Opening the file in OpenAnyFile shows that signature in the file-details panel, so a file renamed to .psb by mistake is easy to spot.
Is it safe to open a PSB file online?
With OpenAnyFile, yes, because nothing is uploaded. The file is read locally through your browser's File API and never leaves your device, so there is no server copy to leak, log or retain. That matters most for the kind of file people are least willing to hand to a random converter site.
What is a .psb file, exactly?
Photoshop Large Document — an image/vnd.adobe.photoshop format created by Adobe since 2003. Same structure as PSD with 64-bit offsets, raising limits to 300,000 px and 4 exabytes. Almost nothing outside Adobe reads it.
Does the same viewer handle formats related to PSB?
Yes — the same engine also opens .psd, so you can compare related files without switching tools.
Related formats
These open with the same engine, so if you have one of these sitting next to your .psb file, it will open too: