File count changes transfer strategy
rsync, archive creation, SFTP and control-panel tools behave differently when the site contains hundreds of thousands of files.
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Free WordPress Tool
WordPress Media Library Migration Estimator
Estimate transfer complexity for large WordPress media libraries using storage size, file count and thumbnail multiplication.
Free to useNo account requiredRuns in your browser
Planning result
Ready
Adjust the inputs to generate a planning recommendation.
Technical explanation
How to interpret this tool before a WordPress migration
Large WordPress media libraries create two different migration problems: bytes to transfer and files to enumerate. Thousands of original images can become many more thumbnail files, and small-file overhead can make transfer behavior very different from a single archive of the same total size.
Offloaded media changes scope
S3-compatible object storage or CDN offload may mean the uploads directory is not fully local. Confirm what actually needs to move.
Regeneration is not always free
Regenerating thumbnails after launch can consume CPU, I/O and time. Decide whether to migrate existing derivatives or recreate them deliberately.
Practical questions
Should I zip the uploads folder?
Often an archive is faster for many small files, but source disk space and extraction capacity must be available.
Can I regenerate thumbnails instead?
Sometimes, but custom sizes, old theme sizes and very large libraries can make regeneration expensive.
What should I verify after migration?
Media URLs, permissions, attachment pages, image sizes, CDN/offload configuration and a sample of old and recent uploads.