Before remote working became mainstream, home broadband was primarily used for streaming, social media, and occasional file downloads — activities that are relatively tolerant of modest bandwidth and brief interruptions. Working from home changes the profile entirely: video conferencing requires consistent, low-latency throughput; corporate VPNs add bandwidth overhead; cloud storage sync runs in the background continuously; and the children doing homework on the same connection add to the load. The question "what speed do I need?" became considerably more complicated when the office moved to the spare bedroom.
Understanding Broadband Speed Units
Before calculating requirements, the unit confusion needs addressing. Broadband speeds are quoted in Megabits per second (Mbps). File sizes and download progress are typically shown in Megabytes (MB). These are different by a factor of 8: 1 Megabyte = 8 Megabits. An 80 Mbps connection downloads at approximately 10 MB per second (80 ÷ 8 = 10).
This distinction matters when calculating download times and comparing ISP claims to real-world experience. A 100 Mbps connection sounds impressive; it downloads at about 12.5 MB/s, meaning a 1 GB file downloads in roughly 80 seconds under ideal conditions. Use our internet speed calculator to translate between Mbps figures and real-world download times for files of any size.
How Much Speed Does Each Activity Use?
Typical bandwidth requirements per activity:
- Video call (HD, Zoom/Teams standard): 3–5 Mbps per active stream (upload and download)
- Video call (4K/high quality): 10–25 Mbps per stream
- File download from cloud storage: As much bandwidth as available (background sync throttles to ~2–5 Mbps on most platforms)
- VPN connection: Adds 10–20% overhead to all traffic; effective speed through most VPNs is 60–80% of underlying connection speed
- Streaming (Netflix 4K): 25 Mbps per stream
- General web browsing and email: 1–2 Mbps
- Video streaming (HD, 1080p): 5–8 Mbps per stream
Calculating Your Household Requirement
The approach: list all devices and activities likely to be running simultaneously at peak household usage, sum the bandwidth requirements, then add a 25–30% headroom margin for unexpected spikes, automatic updates, and background processes.
Example home office household: two adults working from home (one with frequent video calls, one with mostly email and document work), two children on school devices during the day, plus occasional streaming in the evening.
Peak daytime requirement: Adult 1 video call (5 Mbps) + Adult 2 browsing/email (2 Mbps) + Child 1 school video (5 Mbps) + Child 2 school browsing (2 Mbps) + cloud sync background (3 Mbps) = 17 Mbps baseline. With 30% headroom: approximately 22 Mbps. A 30 Mbps connection handles this comfortably; a 50+ Mbps connection provides significant surplus for other activities.
For the evening peak: both parents on video calls simultaneously (10 Mbps) + two children streaming (10–16 Mbps) + general background = 25–30 Mbps baseline plus headroom. A 40–50 Mbps connection is the realistic minimum; 80–100 Mbps is comfortable.
Upload Speed: The Often-Forgotten Half
ISP marketing focuses on download speed because it's higher on most consumer connections. For home workers, upload speed matters equally or more: video conferencing sends your video upstream; file uploads to cloud storage or client servers use upload; sending large attachments uses upload bandwidth.
Typical asymmetric broadband (ADSL, standard FTTC): download 30–80 Mbps, upload 5–20 Mbps. If you're regularly uploading large files or running back-to-back video calls, your upload speed may be the actual constraint — not the download speed the ISP headline advertises.
Full-fibre broadband (FTTP) provides symmetric or near-symmetric speeds on many plans: 150/150, 300/50, or 500/500 Mbps packages are widely available from 2024 onwards. For consistent video calling and heavy cloud usage, full fibre is the right infrastructure.
VPN: What It Does to Your Speed
Corporate VPNs route all your work traffic through the employer's network before it reaches the internet. This creates two speed penalties: the encryption overhead (typically 10–20% reduction) and the routing detour through the corporate server (which may be geographically distant). If your corporate VPN server is in London and you're in Edinburgh, traffic to a Manchester-based service travels London–Manchester–London rather than directly.
If your VPN-connected speeds feel inadequate, run a speed test with VPN on versus VPN off (available through our internet speed calculator guidance). If the VPN substantially reduces speed, discuss with your employer's IT team — there may be a split-tunnelling option that sends only corporate traffic through the VPN while direct internet traffic bypasses it.
Latency Matters as Much as Speed for Calls
Video and voice calls are sensitive to latency (delay) and packet loss, not just bandwidth. A 100 Mbps connection with 200ms latency will produce worse video call quality than a 20 Mbps connection with 15ms latency. Latency is mostly determined by connection type (fibre has lower latency than cable; 5G home broadband has higher latency than fixed line) and distance to the exchange or cabinet.
If you experience choppy video or audio despite apparently adequate download speed, run a latency and packet loss test rather than assuming you need more bandwidth. Ofcom's Connected Nations report at ofcom.org.uk provides useful data on broadband performance by technology type and region for UK households.