Bulk Offline Conversion
Offline conversion is the fastest way to optimize a large image library without burning server resources. It's ideal for migrations and for teams that want consistent quality settings before images ever reach WordPress.
When to Use Offline Conversion
- You are migrating a large media library
- Your host times out during bulk optimization
- You want consistent compression settings across a project
Tooling Options
- Desktop tools (batch export workflows)
- CLI tools (ImageMagick,
cwebp, etc.)
note
This docset references Eagle.cool in a few places, but the workflow applies to any batch conversion tool.
Workflow (Safe)
- Back up originals.
- Export a new optimized folder (do not overwrite originals).
- Spot-check quality on retina screens.
- Upload optimized images.
- Confirm WordPress emits responsive sizes and that the LCP image is optimized.
Common Mistakes
| Mistake | Why It Hurts | Fix |
|---|---|---|
| Over-compressing product photos | Quality loss is visible | Use a higher quality setting for products |
| Renaming files unnecessarily | Breaks references | Preserve filenames where possible |
| Losing transparency | PNG -> lossy conversion | Use a format that preserves transparency when needed |