How much mobile data do you need for a trip?

Plan for 0.35 GB to 1.8 GB of mobile data per day. The low end covers maps and messages, the high end covers daily video and remote work. Multiply your daily figure by the number of days and round up to the next plan size.

What each activity uses

The figures below come from what each service publishes about itself. Where a service gives a bitrate, we converted it to data per hour (1 Mbps sustained for an hour is 450 MB).

Two notes on reading this table. The YouTube rows are built from the connection speed YouTube recommends for each resolution, so treat them as a ceiling: real usage is usually lower. And calls count twice, because your phone uploads your picture while downloading the other person's.

Maps, messaging and social feeds

Neither Google nor WhatsApp publishes a per-hour figure for maps or text messages, so we do not quote one. Text and map tiles are small next to anything in the table above. What moves the number is media: photos and videos that download automatically in chats, and feeds that play video as you scroll. A feed full of autoplaying clips behaves like the video rows, not like messaging.

Tethering a laptop

A laptop on your phone's hotspot does not know it is on a small travel plan. It syncs files, downloads updates and loads desktop versions of sites. Netflix in a browser on its High setting uses up to 3 GB per hour in HD. If you plan to work from a laptop, start from the High profile below and read the hotspot guide first, because some plans restrict sharing.

Three daily profiles

These are the three figures the route calculator uses to turn days into GB.

To give the numbers a scale: 0.35 GB is what about 80 minutes of Netflix on the Automatic mobile setting uses. 0.8 GB is about an hour and a half of one-to-one video calling at Zoom's standard quality. 1.8 GB is about 100 minutes of the same call at 720p.

What the profiles assume

They are planning averages for a whole trip, not measurements of your phone. A heavy day is expected to be offset by a light one. They assume you have Wi-Fi where you sleep and that backups, app updates and big downloads wait for it. They assume mobile data for one phone. A second device on the hotspot is extra unless you pick High.

They also do not fit every kind of plan. Some unlimited plans slow down after a daily amount of full-speed data, and for those the question is what you use on your heaviest day, not the trip average.

If you want a figure based on your own habits, your phone already has one. Both iOS and Android show mobile data used per app in the mobile network settings. Divide the total by the number of days it covers and compare it with the table.

Totals for common trip lengths

Plans come in fixed sizes, so you will buy the next size up. On a route with several countries the total can be split across plans. The calculator does that arithmetic per stop, and regional versus local eSIMs explains how the split is chosen.

How to use less

Download maps before you leave

Google Maps lets you download an area and navigate inside it without a connection. Driving directions work offline. Transit, cycling and walking directions do not, and there is no live traffic. Downloaded areas expire and Maps tries to refresh them over Wi-Fi.

Keep backups and media downloads on Wi-Fi

On an iPhone, Low Data Mode turns off Background App Refresh, automatic downloads and backups, pauses iCloud Photos updates and lowers streaming quality. You find it in Settings, Cellular, Cellular Data Options, and with two lines you set it for the travel line. WhatsApp has a separate media auto-download setting for mobile data, Wi-Fi and roaming. Set mobile data and roaming to download nothing.

Lower video quality on mobile

Netflix's Save Data setting stretches a GB to about 6 hours of viewing. Its Wi-Fi Only setting removes the risk entirely. Download episodes and playlists at the hotel if you want them on a train.

Tell the laptop it is on a limited connection

On Windows 11, open Settings, Network and internet, Wi-Fi, select the hotspot network and turn on Metered connection. Windows Update then downloads only priority updates and Microsoft Store downloads may pause.