Video uses roughly 1 GB per hour in standard definition, up to 3 GB per hour in HD and up to 7 GB per hour in 4K. Those are Netflix's own figures, and other services land in the same range. Music is far lighter: Spotify's highest standard quality works out to about 0.14 GB per hour.
If you know a stream's speed in Mbps, you can work out the data yourself: GB per hour ≈ Mbps × 0.45.
The formula
A stream running at 1 Mbps sends 1 megabit every second. In an hour that's 3,600 megabits. Divide by 8 to get megabytes (450 MB), then by 1,000 for gigabytes:
1 Mbps × 3,600 seconds ÷ 8 ÷ 1,000 = 0.45 GB per hour
So any bitrate times 0.45 gives gigabytes per hour:
| Stream speed | Data per hour |
|---|---|
| 0.32 Mbps (320 kbps music) | about 0.14 GB |
| 3 Mbps | about 1.35 GB |
| 5 Mbps | about 2.25 GB |
| 15 Mbps | about 6.75 GB |
| 25 Mbps | about 11.25 GB |
One catch: services publish recommended connection speeds, not the actual bitrate of their streams. A stream usually runs below the recommendation, because the recommendation includes headroom. Speeds multiplied by 0.45 are therefore upper bounds, not exact usage. Netflix shows this nicely: its 4K recommendation of 15 Mbps works out to 6.75 GB per hour, and Netflix's own 4K data figure is up to 7 GB. Mbps vs MB/s explains why the divide-by-8 step matters.
Netflix
Netflix publishes data use per hour, per device, for each of its playback settings:
| Netflix setting | Data per hour |
|---|---|
| Low (basic quality) | up to 0.3 GB |
| Medium (standard quality) | up to 0.7 GB |
| High, standard definition | up to 1 GB |
| High, HD | up to 3 GB |
| High, 4K | up to 7 GB |
On phones, Netflix's mobile settings put it another way: "Save Data" gives about 6 hours per GB, "Automatic" about 4 hours per GB, and "Maximum Data" can use 1 GB every 20 minutes or more. You can change both in your Netflix account and app settings. For the speed side, see internet speed for Netflix.
YouTube and other video services
YouTube, Hulu and Disney+ publish recommended speeds rather than data figures. Multiplying by 0.45 gives the most each could use per hour, so real use is usually lower:
| Service and quality | Recommended speed | Upper bound per hour |
|---|---|---|
| YouTube 480p | 1.1 Mbps | about 0.5 GB |
| YouTube 720p | 2.5 Mbps | about 1.1 GB |
| YouTube 1080p | 5 Mbps | about 2.25 GB |
| YouTube 4K | 20 Mbps | about 9 GB |
| Hulu streaming library | 3 Mbps | about 1.35 GB |
| Hulu live TV | 8 Mbps | about 3.6 GB |
| Hulu 4K | 16 Mbps | about 7.2 GB |
| Disney+ 4K | 25 Mbps | about 11.25 GB |
The speeds come from YouTube's help center, Hulu's speed recommendations and Disney+'s recommended speeds. Treat the right-hand column as a ceiling for planning, not a measurement. Internet speed for YouTube covers what each quality needs to play smoothly.
Music and podcasts
Audio is tiny by comparison. Spotify's audio quality settings run from about 24 kbit/s on Low to about 320 kbit/s on Very high. Using the same formula:
- Low (24 kbit/s): about 0.01 GB, or 11 MB, per hour
- Normal (96 kbit/s): about 0.04 GB per hour
- High (160 kbit/s): about 0.07 GB per hour
- Very high (320 kbit/s): about 0.14 GB per hour
Lossless is the exception. Spotify recommends a steady 1.5 to 2 Mbps for lossless listening, which is up to about 0.9 GB per hour, as much as low-quality video. Video podcasts count as video, not audio.
Planning around a data cap or mobile plan
Divide your allowance by the hourly figure. Some examples, using Netflix's numbers:
- A 1 TB monthly home cap: 1,000 ÷ 7 ≈ 140 hours of 4K Netflix, or 1,000 ÷ 3 ≈ 330 hours of HD.
- A 20 GB mobile plan: 20 ÷ 3 ≈ 6.7 hours of HD Netflix, or about 120 hours on "Save Data" (20 × 6).
- A family streaming 4 hours of 4K a night: 4 × 7 × 30 = 840 GB a month from that alone.
The quickest savings come from dropping 4K to HD on smaller screens, setting phones to a data-saver mode, and downloading shows on home Wi-Fi before a trip. On a phone, the quality setting matters far more than connection speed: a 5G phone and a 4G phone use the same data for the same video.
Data use and speed are separate questions. A speed test measures how fast data can arrive, and it uses a little data itself. If you're checking whether your mobile connection can handle HD before you start a long stream, a mobile data speed test is the quick way to find out.
Common questions
Does a faster internet plan use more data?
Not by itself. Data use depends on what you watch and at what quality. A faster plan can let apps pick a higher quality automatically, which does use more.
Do downloaded shows use less data than streaming?
Downloading uses roughly the same data as streaming the same quality, but you choose when it happens. Download on Wi-Fi at home and you won't touch your mobile allowance when you watch later.