Bufferbloat

What is bufferbloat?

Bufferbloat happens when network equipment (like your router or modem) holds onto too much data in its memory buffers instead of sending it right away. This creates unexpected delays that don't show up on regular speed tests.

Imagine a water pipe: instead of water flowing straight through, there's a huge tank in the middle. Water goes in quickly, but it takes a while to fill the tank before anything comes out the other side. Your internet connection can work the same way—data piles up in buffers, adding seconds of delay.

Why it matters

Bufferbloat is especially frustrating because your speed test looks fine. You have fast download and upload speeds, but video calls still lag, online games are unplayable, and everything feels sluggish when someone else is using the internet.

The problem gets worse when your connection is busy. Uploading photos, streaming video, or running backups can trigger bufferbloat, causing your video call to suddenly lag even though you have "plenty of bandwidth."

What you can do

Before an important call:

• Ask others in your household to pause large downloads, game updates, or 4K streaming
• Pause any cloud backup or sync services (Dropbox, Google Drive, iCloud)
• Avoid uploading large files or photos during your call

Long-term fixes:

• If you've been renting a modem from your cable company for years, buying a newer model (like a current Arris or Motorola) often helps—older modems are worse at handling multiple users
• Upgrading from DSL or cable to fiber usually eliminates bufferbloat entirely
• Gaming routers (like those from ASUS or Netgear) often include features specifically designed to prevent bufferbloat
• If your router has a "QoS" or "Quality of Service" setting, enabling it can help prioritize video calls

What Network Weather shows you

Network Weather tests for bufferbloat by measuring latency while your connection is under load.