fast-copy vs FastCopy
First, the disambiguation: FastCopy is a well-established Windows copy tool by Shirouzu Hiroaki, around since 2004 — fast-copy (this project) is an unrelated, Apache-2.0 licensed CLI for Linux, macOS and Windows. The similar names are an accident of both tools wanting the same thing: copies that are faster than what the OS ships with. They get there very differently.
The measured difference
Same workload, same machine: 9,578 files / 890.8 MB, USB 2.0 external HDD to internal SSD (NTFS), Windows 11, full reboot before each run, Windows Defender active for both tools:
| Tool | Time | Verification |
|---|---|---|
| fast-copy | 2 m 28 s | ON — every file hash-checked |
| FastCopy 5.11 | 3 m 38 s | off |
fast-copy did the verification pass and still finished more than a minute ahead. Full methodology here.
Feature differences that matter
| fast-copy | FastCopy | |
|---|---|---|
| Platforms | Linux, macOS, Windows | Windows (macOS port exists) |
| License | Apache-2.0, fully free | GPL-ish source, donation-ware |
| Read strategy | physical-offset sorted + small-file bundling | large parallel buffers |
| Post-copy verification | on by default | optional |
| Content dedup → hard links | yes, cached across runs | no |
| SSH / S3 / Azure / GCS targets | built in | no (local & SMB paths) |
| Sparse files / VM images | SEEK_DATA-aware, holes preserved | no special handling |
| Shell integration | no | yes |
When FastCopy is still the better tool
Honest answer: it's a 20-year-old, battle-hardened Windows native with Explorer integration and fine-grained include/exclude filters that many admins know by heart. If your world is Windows-to-Windows local and SMB copies and you rely on its filter syntax, it remains a fine tool. fast-copy earns its place when you want the same job to also run on Linux servers and NAS boxes, push over SSH or to object storage, deduplicate, and hand you a hash-verified result by default.
Download fast-copy · Windows install & SmartScreen notes: /install/windows/
Also compared: fast-copy vs rsync · fast-copy vs cp · fast-copy vs scp / SFTP · fast-copy vs Robocopy · fast-copy vs TeraCopy · full benchmark methodology