> For the complete documentation index, see [llms.txt](https://moverdocs.files.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://moverdocs.files.com/migration-guide/dry-runs.md).

# Dry Runs

A dry run previews a migration without copying or deleting data. It lists the source and destination and applies the same path matching, size comparison, filters, and filename validation as a live run. It reports file and folder counts, estimated transfer size, and conditions such as excluded patterns, case conflicts, unsupported filenames, excessive folder depth, or too many items in one folder. Dry runs do not count against your [usage pack](/billing-and-usage-packs.md).

The scan still makes listing and metadata requests to both connections. A provider can therefore rate-limit a dry run even though no file data is transferred. If that happens, use the batching recommendations in [Performance and Rate Limits](/migration-behavior/performance-and-rate-limits.md).

A dry run is a snapshot, not a reservation. Files added, removed, renamed, or changed after the scan affect the live run. Mover does not compare checksums during a dry run, so a source and destination file with the same name and reported size is treated as already present even if their contents differ.

Run a dry run before every live migration. Review the file-level results to confirm that filters work as intended, resolve errors, and choose a [usage pack](/billing-and-usage-packs.md#usage-packs) based on the expected transfer size.