Netflix is one of the biggest consumers of home and mobile data worldwide, and the amount it uses depends almost entirely on picture quality. Netflix adjusts its stream automatically based on your connection, device and account settings, so two people watching the same episode can use very different amounts of data.
As a rough guide, standard definition uses around 0.7 GB per hour, HD around 3 GB per hour, and Ultra HD (4K) up to 7 GB per hour. That means a two-hour movie in 4K can use as much data as a whole week of light mobile browsing. If several people in your home watch at the same time on different screens, each stream counts separately.
On a mobile plan, the easiest way to cut usage is the 'Save data' option in the Netflix app's mobile data settings, which caps streams at roughly 0.3 GB per hour. Downloading episodes over Wi-Fi before you travel is another reliable way to avoid surprise overages. On a home connection, setting playback to 'Medium' in your profile settings limits usage to SD quality.
Your Netflix plan also matters: the cheaper tiers are limited to HD, while the premium tier unlocks 4K and HDR. If you only watch on a phone or laptop, the difference in visible quality is small, but the data difference is large. Use the calculator above to compare scenarios — change the quality per service, adjust hours per day, and set the number of devices streaming at once.
The results show your estimated daily, monthly and yearly total, plus a recommended data tier so you know whether a 50 GB, 100 GB or unlimited plan is the right fit for your household.