Broadband Speed Calculator (how many Mb/s does my household need?)
Count what happens at the same time on your busiest evening. The calculator adds it up, leaves room for Wi-Fi and peak-time slowdowns, and tells you the plan that's comfortable, then checks the one you have.
What happens at the same time at your busiest moment?
Check your plan
Use the peak-time or minimum guaranteed speed from your provider, or a speed test on a cable at about 9 pm. Leave blank to just see what you need.
Download pipe
Upload pipe
Coloured blocks are what's in use, the striped part is headroom, and the white line is your plan.
Where a faster plan does show: big downloads
| Speed | Time for 100 GB | At a realistic 70% of it |
|---|
How it works
Use the + and − buttons to count what happens at the same time at your busiest normal moment, usually a weekday evening. It's the overlap that matters, not how many phones and TVs you own: five people who each watch HD at different times only ever need one stream's worth. Each row shows the typical figure it adds, for example about 25 Mb/s for a 4K stream, 5 Mb/s for HD and 4 Mb/s each way for an HD video call.
The total is then multiplied by a headroom factor. Wi-Fi rarely gives every room the full line speed and providers' shared networks give a little less at peak time, so ×1.5 suits most homes. Pick ×1.25 if most heavy use is on a cable, or ×2 for weak Wi-Fi or a network that's known to slow down in the evening. The suggested plan is the first common speed tier at or above that figure.
Type your plan's speeds to check your plan. Use the peak-time or minimum guaranteed speed rather than the headline one, or run a speed test on a cable at about 9 pm. Plenty means it covers the headroom figure, tight means it covers what's in use but not the headroom, and not enough means something will drop to a lower quality or stall. The pipes show each activity as a coloured block, the headroom as stripes and your plan as a white line.
Streaming and calls stop improving once they have what they need, so the main reason to pay for more is big downloads. The last table shows how long one takes at your speed and common tiers, both in theory (GB × 8,000 ÷ Mb/s seconds) and at a realistic 70% for Wi-Fi and busy servers.
The figures are typical published recommendations, rounded; apps adjust their quality to what's available, so treat the result as a guide. Everything runs in your browser. Your household is saved only in the page address so you can copy a link, and nothing is sent anywhere. Background: how much broadband speed do I need, contention ratios, Mbps vs MB/s and the streaming data calculator for data caps. For a playful version, Wirebook's street of pipes shows how a shared connection is split. Need the same sum in a script or a comparison page? Anvil's free broadband speed API returns the busiest-moment Mb/s, the suggested plan, the verdict on your plan and download times as JSON, with no key.
Questions
How much broadband speed do I need?
Add the things that happen at the same time at your busiest moment (about 25 Mb/s per 4K stream, 5 per HD stream, 4 per video call, 5 per online game, 2 for browsing), then add about half again. Most one or two person homes are fine on 30 to 50 Mb/s and a busy family on 80 to 150 Mb/s.
Is 50 Mb/s enough for a family of four?
Usually, unless two or more 4K streams overlap. A 4K TV, an HD tablet, a video call, an online game and browsing add up to about 41 Mb/s, or about 62 Mb/s with headroom, so 50 Mb/s is tight at the busiest moment and 80 Mb/s is comfortable.
Is 100 Mb/s enough?
For most homes, yes: it covers about three 4K streams at once with headroom, or a family's usual evening several times over. Faster plans mainly shorten big downloads.
What upload speed do I need?
About 4 Mb/s for each HD video call happening at the same time and 6 to 10 Mb/s if you stream yourself live. 10 to 20 Mb/s is comfortable for one or two people working from home; cloud backups go faster with more.
Is gigabit broadband worth it?
Mainly if you download very large files often or lots of heavy users overlap. A 100 GB game takes about 2 h 13 min at 100 Mb/s and about 13 min at 1 Gb/s, but streams and calls look the same on both.
Is anything I enter sent anywhere?
No. The page only does arithmetic in your browser. Your household is kept in the page address so you can share a link, and nothing is stored or uploaded.