What “flattened PNG” means
A PSD can contain many layers, groups, masks, and adjustment layers. A flattened PNG is a single image of the document as composited. When the file contains a composite preview (the usual result of saving with Maximize Compatibility in Photoshop), Layerzip uses that preview. That is more reliable than trying to re-blend every layer in the browser.
If you instead need one PNG per layer, use Extract layers from a PSD (a paid feature).
Limits you should know
- Free plan: one flattened export at a time, files up to 30 MB and 8,000 px on the long edge. Paid plans raise this to 200 MB and 12,000 px and add batch jobs (Pricing).
- Color: RGB documents work best. CMYK is converted with an approximate profile, not your embedded ICC profile, so print colors may shift.
- Bit depth: 16-bit and 32-bit files can often be read; the PNG you download is 8-bit.
- Smart objects and adjustments: not every effect is reproduced if we have to rebuild the image without a composite.
- Very large canvases may fail with a memory error. That is a browser limit, not a quota we can fully remove.
- PSB (Photoshop Large Document) files open within the same limits; we tested Photoshop-saved PSB samples. Huge PSBs, the reason the format exists, usually exceed browser memory.
Need a smaller, lossy file for a preview or a web mockup? Use PSD to JPG.
Why a browser converter instead of an online upload tool
Many “PSD to PNG online” sites send the document to a server, convert it, then let you download the result. That is convenient, but it means a third party processes your artwork. Layerzip keeps the bytes in your tab. Trade-off: we depend on what is already stored in the file, and we will not match Photoshop’s renderer in every edge case. A longer comparison is on Convert a PSD without Photoshop and PSD to PNG online.