The short answer
- PSD is an image-design format that preserves Photoshop layers, masks, effects, and other editing features, with a 2 GB file-size limit.
- Open a PSD in a current version of Adobe Photoshop when its editable Photoshop features must be retained. Compatible Adobe applications such as Illustrator, InDesign, Premiere, and After Effects can also work with PSD files. A saved composite image can improve opening speed and compatibility with other applications or older versions, but rendering may differ if software must reconstruct the image from layer data.
- Treat an unfamiliar PSD as untrusted structured input. The extension alone does not establish safety, and PSD contains variable-length and compressed sections. Adobe has documented critical Photoshop vulnerabilities involving crafted files, user interaction, and possible arbitrary code execution, so use current, patched software and avoid opening unexpected files.
PSD File: How to Open, Check, and Convert Adobe Photoshop Documents
Adobe Photoshop Document (PSD) is Photoshop’s native and default document format. A version 1 PSD contains a header, color-mode data, image resources, layer-and-mask information, and image data. It can store 1–56 channels, dimensions up to 30,000 × 30,000 pixels, and depths of 1, 8, 16, or 32 bits per channel across Adobe-specified color modes.
Exporting PSD to JPEG, PNG, or flattened TIFF can discard editable layers, masks, effects, and Photoshop-specific features. Keep the original PSD—or PSB for a document beyond PSD limits—when future editing matters. Renaming .psb to .psd does not convert the file.
How to open it
Open a PSD in a current version of Adobe Photoshop when its editable Photoshop features must be retained. Compatible Adobe applications such as Illustrator, InDesign, Premiere, and After Effects can also work with PSD files. A saved composite image can improve opening speed and compatibility with other applications or older versions, but rendering may differ if software must reconstruct the image from layer data.
Open a PSD in a current version of Adobe Photoshop when its editable Photoshop features must be retained. Compatible Adobe applications such as Illustrator, InDesign, Premiere, and After Effects can also work with PSD files. A saved composite image can improve opening speed and compatibility with other applications or older versions, but rendering may differ if software must reconstruct the image from layer data.
Exporting PSD to JPEG, PNG, or flattened TIFF can discard editable layers, masks, effects, and Photoshop-specific features. Keep the original PSD—or PSB for a document beyond PSD limits—when future editing matters. Renaming .psb to .psd does not convert the file.
File safety
Treat an unfamiliar PSD as untrusted structured input. The extension alone does not establish safety, and PSD contains variable-length and compressed sections. Adobe has documented critical Photoshop vulnerabilities involving crafted files, user interaction, and possible arbitrary code execution, so use current, patched software and avoid opening unexpected files.
An unknown sender, a name ending in two extensions, or contents that do not match the extension — check before you open it.
Converting it
Exporting PSD to JPEG, PNG, or flattened TIFF can discard editable layers, masks, effects, and Photoshop-specific features. Keep the original PSD—or PSB for a document beyond PSD limits—when future editing matters. Renaming .psb to .psd does not convert the file.
Convert a copy, never the original, then compare quality, metadata, and layout against what you started with.
Common questions
What is a PSD file and what is it used for?
PSD is Adobe Photoshop’s native document format. It is used to retain layers, masks, effects, and other Photoshop editing capabilities instead of storing only a flattened image.
How do I open a PSD file for editing?
Open it in a current version of Adobe Photoshop. Illustrator, InDesign, Premiere, and After Effects are also compatible Adobe applications, although a saved composite improves compatibility and opening speed.
How do I open a PSD file on Windows?
Use a current Windows version of Adobe Photoshop and open the .PSD file there. If the file came from someone else, treat it as untrusted and update Photoshop before opening it.
How do I open a PSD file on Mac?
Use a current macOS version of Adobe Photoshop. Other compatible Adobe applications can work with PSD, but a composite saved in the document improves compatibility.
Why will a PSD file not open or render correctly?
Check that its header starts with ASCII 8BPS and version 1, represented by 38 42 50 53 00 01; Adobe says readers should reject a mismatched signature or version. A missing merged composite can also require software to reconstruct the result from layers, which may render differently.
What is the difference between PSD and PSB, and which should I use?
PSD is Photoshop’s version 1 native format and is limited to 2 GB and 30,000 pixels in either dimension. PSB is the distinct Large Document Format recommended for larger documents; use PSD within its limits and PSB when those limits are exceeded.
Can I convert PSD to PNG without losing layers?
A conventional PNG does not preserve the full set of editable Photoshop layers, masks, effects, and Photoshop-specific features described for PSD. Keep a PSD or PSB copy and use PNG as a delivery copy.
Is an unfamiliar PSD file safe to open?
Do not assume so from the .PSD extension. Adobe has documented critical Photoshop vulnerabilities triggered through crafted input with user interaction, so open unfamiliar PSD files only in current, patched software and only when you trust the source.
What are the PSD file size, dimension, channel, and bit-depth limits?
PSD is limited to 2 GB, 1–30,000 pixels in each direction, 1–56 channels, and 1, 8, 16, or 32 bits per channel. Adobe recommends PSB for documents beyond PSD limits.
Does a valid 8BPS PSD header prove that the file is safe and will render correctly?
No. The header identifies a version 1 PSD, but it does not establish that the remaining variable-length data is trustworthy or that every application will reproduce the same composite image.
Related formats
Sources
Adobe Photoshop File Formats Specification · Adobe
Image file formats supported in Photoshop · Adobe
Photoshop file formats overview · Adobe
Adobe Photoshop Family · Library of Congress
IANA Media Types Registry · IANA
Adobe Security Bulletin APSB25-40 · Adobe Product Security Incident Response Team