How much data does YouTube use?

Why there is no official number

YouTube's help pages explain the quality options but never translate them into megabytes. The closest they come is the description of each option: Higher picture quality uses more data, Data saver gives lower picture quality. That is not an oversight. The same hour can be a 4K documentary on a big phone or a talk show at low resolution, and Auto moves between levels as the connection changes.

So any per-hour figure you see quoted online is someone else's measurement on someone else's settings. On a data plan, the useful approach has two steps: fix the quality on mobile networks so the app stops deciding for you, then measure what that setting costs on your phone. Both take a few minutes.

Choose the quality for mobile networks

Tap your profile picture, then Settings, then Video quality preferences. YouTube lets you pick one quality for mobile networks and another for Wi-Fi, with four options in each: Auto, which adjusts to your conditions; Higher picture quality, which uses more data and may take longer to start; Data saver, lower picture quality but videos may start faster; and Advanced, to pick a resolution yourself.

For a trip, Data saver on mobile networks and whatever you like on Wi-Fi is the simple setup. If one video needs more detail, a map in a travel vlog or a recipe, change it just for that video from the player: Settings, then Quality. The default for the rest stays where you left it.

Three background habits to switch off

• Playback in feeds: Settings, General, Playback in feeds. YouTube says it may be on by default on Wi-Fi and mobile data; choose Wi-Fi only or Off.
• Autoplay: the switch at the top of the player, or Settings, Autoplay. On a mobile network YouTube stops it after 30 minutes of inactivity, against 4 hours on Wi-Fi.
• Uploads: Settings, General, Uploads, then choose Wi-Fi so a video you post waits for the hotel.

None of these shows up as watching. Playback in feeds plays videos while you scroll the Home tab and search results; Autoplay keeps the next video coming after the one you chose. Switching both to Wi-Fi only or off removes the data you spend on videos you never meant to watch.

Measure your own hour in 15 minutes

• iPhone: Settings, Cellular (or Mobile Data), scroll down and tap Reset Statistics.
• Pixel and stock Android: Settings, Network & internet, SIMs, App data usage.
• Samsung Galaxy: Settings, Connections, Data usage, Mobile data usage.

Reset the counter where you can, switch off Wi-Fi and watch 15 minutes of the kind of video you watch on holiday with Data saver on mobile networks. Read the YouTube line and multiply by four. Repeat with Auto if you want to see the difference. Apple and Google both note that the phone's count can differ slightly from the operator's, so round up.

Downloads take YouTube off the data plan

The way to watch on a bus or a plane without spending data is to download at home. That is a YouTube Premium feature, and downloaded videos play offline for up to 29 days before the app needs to reconnect, or 48 hours in some countries. The download quality is chosen separately in Settings, and higher quality uses more data and more storage. The guide to downloading before a flight goes through it with Netflix and Spotify too.

If you are deciding between platforms for evening viewing, Netflix is the one that does publish figures per setting; the Netflix data guide lists them.

Where YouTube fits in a trip estimate

Video is what decides the size of a data plan, much more than maps or messages. The data calculator on this site adds video on top of everyday use: about 250 MB a day if you watch now and then, and about 900 MB a day for a couple of hours. Those are the site's estimates for typical use, not Google figures, and your 15-minute test is a better guide for your own habits.

Children watching on a tablet through your hotspot are a common surprise, because the tablet has its own YouTube settings. Set Data saver there too, or follow the guide to sharing data with kids' tablets.