Convert Mbps, Kbps, Gbps, and MB/s, or estimate download time for a file based on connection speed and network efficiency settings.
- Bandwidth Calculator
- Upload Time Calculator
- Bandwidth Delay Product Calculator
- Throughput to IOPS Calculator
- All Unit Converters
Mbps Formula
The calculator uses two core formulas depending on the tab you select.
Convert speed (bits to bytes and back):
MB/s = Mbps / 8
Mbps = MB/s * 8
Download time:
Time (seconds) = (File size in bits) / (Speed in bps * Efficiency)
- Mbps: megabits per second (1 Mbps = 1,000,000 bits per second)
- MB/s: megabytes per second, decimal (1 MB = 1,000,000 bytes)
- MiB/s: mebibytes per second, binary (1 MiB = 1,048,576 bytes)
- File size in bits: bytes multiplied by 8
- Efficiency: a decimal between 0 and 1 that accounts for overhead and Wi-Fi loss
The Convert speed tab divides or multiplies by 8 to switch between bit-based units (used by ISPs) and byte-based units (used by browsers and operating systems). It also lets you choose between decimal MB and binary MiB for the byte result. The Download time tab applies the formula above and reduces the rated speed by the efficiency you pick, since real connections rarely hit the advertised number.
Reference Tables
Use these to sanity-check your inputs and the result.
| Mbps | MB/s (decimal) | MiB/s (binary) | 1 GB file (ideal) |
|---|---|---|---|
| 10 | 1.25 | 1.19 | 13 min 20 sec |
| 25 | 3.13 | 2.98 | 5 min 20 sec |
| 100 | 12.5 | 11.92 | 1 min 20 sec |
| 300 | 37.5 | 35.76 | 27 sec |
| 1,000 | 125 | 119.21 | 8 sec |
| Activity | Recommended speed |
|---|---|
| Email and web browsing | 5 Mbps |
| HD video call (one person) | 3 to 5 Mbps |
| 1080p streaming | 5 to 10 Mbps |
| 4K streaming | 25 Mbps |
| Online gaming | 10 to 25 Mbps |
| Household with 4+ devices | 100+ Mbps |
Examples
Example 1: Convert 200 Mbps to MB/s.
Divide by 8: 200 / 8 = 25 MB/s. That is the rate your browser or download manager will show.
Example 2: How long to download a 5 GB game on a 100 Mbps connection?
File size in bits: 5 GB × 1,000,000,000 × 8 = 40,000,000,000 bits. At 100 Mbps (100,000,000 bps), ideal time = 400 seconds, or about 6 min 40 sec. With 90% efficiency, expect roughly 7 min 24 sec.
FAQ
Why is my download speed so much lower than my Mbps plan?
ISPs advertise in megabits, but downloads display in megabytes. Divide by 8 to compare. A 100 Mbps plan tops out near 12.5 MB/s.
What is the difference between MB and MiB?
MB is decimal (1,000,000 bytes). MiB is binary (1,048,576 bytes). Storage and ISPs use MB; some operating systems and apps use MiB but label it MB.
Why use an efficiency setting below 100%?
Real connections lose throughput to Wi-Fi interference, protocol overhead, and server limits. 90% is a reasonable default for a wired or strong Wi-Fi connection.
Is higher Mbps always better?
Only up to a point. Once you exceed what your activities require, extra Mbps does not make pages load noticeably faster. Latency and Wi-Fi quality matter more at that stage.
