METRICS

Understanding the Video Experience Score

The Video Experience Score shows how smoothly YouTube actually played — not peak download speed, but real buffering and frozen frames from real sessions. Higher is better. The same score appears in the Android app and on the live experience map.

What is the Video Experience Score?

Unlike a speed test that measures peak capacity in a single burst, the Video Experience Score captures what actually happened during YouTube playback. It combines how long each buffer event lasted with how many frames were frozen during that stall.

Scores range from 0 to 100. A high score means smooth streaming. A low score means frequent stuttering or long pauses that disrupt viewing. Each map hex shows the aggregated experience across many anonymous YouTube tests in that area — not a single user or speed test.

How a Test Works

BufferBeat runs on your phone. You tap Start YouTube Test, the app opens YouTube, and measures your video experience over a 2-minute session using on-device frame analysis. No video is recorded or uploaded — only anonymous buffering metrics, signal data, and location for the public map.

  1. 1
    Open YouTube BufferBeat launches YouTube and monitors playback in the background while you watch.
  2. 2
    Detect stalls Each buffer event is measured by duration and frozen frames, correlated with carrier signal (RSRP) and GPS.
  3. 3
    Get your score Your Video Experience Score appears in the app. Anonymous aggregates update the public map for your area.

How It's Calculated

Under the hood, BufferBeat computes a Video Frustration Index (VFI) from each session — the stall “burden” normalized by total watch time:

VFI = Σ (duration_ms × frames_frozen) ÷ total_session_time_ms
Each buffer event contributes to the numerator. Sessions with no buffering have VFI = 0.

That internal index is converted to the score you see on the map and in the app:

Video Experience Score = 100 − VFI
VFI is scaled to 0–100 per session (0 = no frustration). We invert it so a higher score always means a better experience on the map and in the app.

Reading the Live Experience Map

The map uses an H3 hex grid. The grid sharpens as you zoom in — from regional overview down to neighborhood and street level. If finer data is not available yet, the map falls back to the nearest resolution with enough samples (shown as “nearest available” in the header).

When you zoom Grid Typical scale
Out (state / country) Region · H3 res 6 ~36 km² per hex
City City · H3 res 7 ~5 km² per hex
Neighborhood Neighborhood · H3 res 8 ~0.7 km² per hex
Street Street · H3 res 9 ~0.1 km² per hex

Click any hex to see sessions, Video Experience Score, rating (Excellent / Fair / Poor), and average RSRP for that area. Filter by country, carrier (Verizon, AT&T, T-Mobile), or use Gap → Congestion only to find strong-signal areas with poor playback.

Privacy: the 5-user rule

A hex only appears on the public map after at least 5 unique anonymous sessions (10 at street / res 9). This K-anonymity rule prevents any single test from identifying a home or workplace. Zoomed-out views may look sparse until an area accumulates enough contributors.

What the Numbers Mean

On the live map, hexes are colored by their Video Experience Score. Here's how to read them:

80–100 · Excellent Smooth streaming — minimal or no buffering
50–79 · Fair Occasional stuttering — some disruption
0–49 · Poor Frequent stuttering or long pauses — viewing disrupted

Congestion vs. Weak Signal

When you see buffering, it can be caused by a weak cellular signal or by network congestion — too many users sharing the same tower. BufferBeat helps distinguish these.

Congestion only filter

Hexes with strong signal (RSRP > -95 dBm) but Fair or Poor experience (VES below 80) often suggest congestion rather than coverage gaps. Use Gap → Congestion only on the live map to focus on these areas — signal is present but playback still stutters.

Why Not Just Use Speed Tests?

Speed tests measure what your connection could do in a short burst. Video streaming depends on sustained throughput, consistency, and how the app and CDN behave over time. Real sessions on YouTube reveal what actually happens — including stalls, rebuffering, and frame freezes that speed tests never capture.

The Video Experience Score is built from actual YouTube viewing sessions, so it reflects the experience that matters: can you watch a video without interruption?