Enter roughly how many hours a day your household spends on each activity, and how many of each happen at the same time at the busiest moment. The calculator estimates your monthly data use and the speed you need.
Your estimate
Plan to look for
25 Mbps · 489 GB a month
You use about 391 GB a month and up to 13.5 Mbps at once; both include 25% headroom in the plan.
Estimated amount to buy
- Download speed
- 25 Mbps
- Monthly data
- 489 GB (or an unlimited plan)
- Speed needed with 25% headroom
- 16.9 Mbps
Calculated quantity (no headroom)
- HD video streaming: 3 h a day
- 273.8 GB a month
- Short videos and social media: 1 h a day
- 30.4 GB a month
- Video calls: 1 h a day
- 45.6 GB a month
- Online gaming (playing, not downloading): 1 h a day
- 3 GB a month
- Music streaming: 2 h a day
- 9.1 GB a month
- Web, email and apps: 2 h a day
- 9.1 GB a month
- Big downloads
- 20 GB a month
- Monthly data
- 391.1 GB
- Busiest-time speed
- 13.5 Mbps
How this was calculated
- Daily data = 3 h × 3 GB + 1 h × 1 GB + 1 h × 1.5 GB + 1 h × 0.1 GB + 2 h × 0.15 GB + 2 h × 0.15 GB = 12.2 GB
- Monthly data = 12.2 GB × 30.42 days + 20 GB downloads = 391.1 GB
- With 25% headroom = 391.1 × 1.25 = 488.9, rounded up to 489 GB
- Busiest time = 1 × 5 Mbps + 1 × 3 Mbps + 1 × 4 Mbps + 1 × 0.5 Mbps + 1 × 1 Mbps = 13.5 Mbps
- With 25% headroom = 16.9 Mbps; the next common plan speed is 25 Mbps
- Wi-Fi often delivers less than the plan speed, especially far from the router. If your connection feels slow, the router’s position can matter as much as the plan.
- Upload speed matters for video calls and cloud backups. Many cable plans have much slower upload than download.
How the internet calculation works
- Monthly data = the sum of (hours per day × data per hour) for each activity × 30.4 days, plus big downloads.
- Speed = the sum of (activities at the same time × the speed each needs) at your busiest moment.
- Both get the headroom added. Data is rounded up to a whole GB, and speed goes up to the next common plan speed (25, 50, 100, 200, 300, 500, 1,000 or 2,000 Mbps).
The figures used
| Activity | Data per hour | Speed each |
|---|
| HD video streaming | 3 GB | 5 Mbps |
|---|
| 4K video streaming | 7 GB | 15 Mbps |
|---|
| Short videos and social media | 1 GB | 3 Mbps |
|---|
| Video calls | 1.5 GB | 4 Mbps |
|---|
| Online gaming (playing, not downloading) | 0.1 GB | 3 Mbps |
|---|
| Music streaming | 0.15 GB | 0.5 Mbps |
|---|
| Web, email and apps | 0.15 GB | 1 Mbps |
|---|
Video figures are close to what major streaming services publish; actual use depends on the service, the device and its quality setting. The other figures are common planning estimates. Many services lower quality automatically on slow connections, so they use less.
Rounding rules
- Monthly data is rounded up to a whole GB after headroom.
- Speed is matched to the next common plan speed up.
