Data Transfer Calculator
Need to know how long a transfer will take? Enter your file size and connection speed to get an instant estimate. This calculator supports speeds from Kbps to Gbps, handles both bit-rate and byte-rate units, and accounts for protocol overhead that reduces real-world throughput.
Real-world transfer speeds are always lower than the advertised connection rate. Protocol overhead (TCP headers, encryption, error correction) typically eats 5-20% of the bandwidth, and network congestion can reduce it further.
Common transfer speed references:
- Wi-Fi 5 (802.11ac): 200-800 Mbps real-world
- Wi-Fi 6 (802.11ax): 500-1200 Mbps real-world
- Gigabit Ethernet: 900-950 Mbps real-world
- USB 3.0: 3-4 Gbps real-world
- Thunderbolt 3: Up to 40 Gbps
- NVMe SSD (internal): 3-7 GB/s
Remember: ISPs and hardware manufacturers advertise in bits (Mbps), while your operating system shows file sizes in bytes (MB). Divide the bit rate by 8 to get the byte rate.