Data transfer time estimator
How long a bulk copy will take at a given link speed and efficiency, for planning migrations and backups.
How it works
Duration = size in bits ÷ (link speed × efficiency). Efficiency covers everything that keeps a transfer below line rate: protocol and encryption overhead, latency, disk speed, and provider rate limits.
The best way to choose an efficiency value is to time a short test transfer over the real path and work backwards.
Size units: MB, GB, and TB are decimal (powers of 1,000); MiB, GiB, and TiB are binary (powers of 1,024).