How much mobile data do you need abroad?
Eight plain questions — no hours to work out, no megabytes to add up. The estimate updates as you answer, and the onesim plan that covers your whole trip appears with it.
How long is your trip?
We only offer packages that stay valid for the whole 10 days.
Which countries are you visiting?
Add every stop. We pick the cheapest package that covers all of them — skip it and you still get the gigabytes.
Nothing selected yet — the estimate below works without it.
How much are you on your phone when you travel?
Maps, messages, a look at the news.
Scrolling social or watching video?
The biggest single factor in any estimate.
Video calls home?
WhatsApp, FaceTime, Zoom.
Music and podcasts?
Downloading on Wi-Fi first saves a surprising amount.
Backing up photos as you go?
iCloud or Google Photos uploading over mobile data.
How many phones share this data?
A hotspot for a laptop counts as one more.
Figures are estimates based on typical app usage — your own use will vary with video quality, signal and how much you do on Wi-Fi. How we calculate this
What actually uses your data
These are the rates the calculator runs on. Video sits in a different league to everything else — one evening of streaming can cost more than a week of maps and messages.
Typical mobile data use per activity, per phone. Estimates.
| Activity | Per hour | An hour a day for a week |
|---|---|---|
| Maps and navigation Google Maps, Apple Maps | 5 MB | 35 MB |
| Messaging, email, browsing WhatsApp, Gmail, Safari | 25 MB | 175 MB |
| Social feeds Instagram, TikTok, X | 500 MB | 3.5 GB |
| Music and podcasts Spotify, Apple Music | 70 MB | 490 MB |
| Video streaming YouTube, Netflix at 480p | 900 MB | 6.3 GB |
| Video calls FaceTime, WhatsApp video | 500 MB | 3.5 GB |
How much data does each app use?
The apps travellers ask about most, and what an hour of each costs you.
TikTok
840 MB / hour
The heaviest common app. An hour a night for a week is close to 6 GB.
500 MB / hour
Reels push it well past a photo feed. Autoplay off saves a lot.
YouTube at 480p
560 MB / hour
At 1080p it is nearer 1.5 GB an hour. Quality is a per-video setting.
Netflix, standard
1 GB / hour
Download episodes on hotel Wi-Fi and this drops to nothing.
Google Maps
5 MB / hour
Navigation is tiny. Offline maps make it near zero.
WhatsApp video call
300 MB / hour
A voice call is about 20 MB an hour. Texts are negligible.
FaceTime
400 MB / hour
A 20-minute call home costs roughly 130 MB.
Spotify, high quality
70 MB / hour
Very high quality doubles it. Downloads on Wi-Fi cost nothing abroad.
What the same trip costs on roaming
Your estimate is 10 GB over 10 days. Bought as roaming day passes from a home operator, a trip that length usually runs to this:
80.00€
10 days × 8.00€ a day, bought from your home operator
How we calculate this
No tracking, no guesswork about you personally — just published app bitrates and common measurements, applied to the answers you give.
- 01Your answers become hours a dayEach choice maps to an hours-per-day figure for a group of activities — “every evening” of feeds and video, for instance, is about 1.5 hours of scrolling and an hour of video.
- 02Hours are multiplied by published ratesThe rates in the table above come from app-published bitrates and commonly reported measurements, not from anyone’s account. We use standard, not maximum, quality.
- 03A daily baseline is addedEvery day carries 30 MB of background activity — notifications, weather, messaging sync. Photo backup, if you turn it on, adds about 90 MB a day for roughly 25 photos and a short clip.
- 04Extra phones add 60% eachA second phone on the same package rarely doubles usage, so each additional device adds about 60% of one phone’s total rather than another 100%.
- 05The range is deliberately wideTight is 30% under the estimate, generous is 40% over. Real use swings with video quality, signal strength and how much of the trip you spend on Wi-Fi.
- 06Then we match a packageWe only offer packages whose validity covers your dates and whose country list includes every stop you picked — then the cheapest one that holds your estimate.
Six ways to use less data abroad
Most of a trip’s data goes on things you can move to Wi-Fi before you leave.
Download offline maps
Save your city in Google Maps or Apple Maps over Wi-Fi. Navigation then costs almost nothing.
Load music and episodes before you go
Downloads on home or hotel Wi-Fi are free. Streaming the same playlist abroad is not.
Turn off photo backup on mobile data
Set iCloud or Google Photos to upload on Wi-Fi only. It is usually the biggest silent drain.
Drop video to 480p
On a phone screen the difference is hard to see and the saving is three-quarters of the data.
Switch off autoplay in social apps
Feeds pre-load video you never watch. One setting, in every app.
Leave big updates for Wi-Fi
App and system updates can run to gigabytes. Pause them until you are back on Wi-Fi.
Watch your usage as you travel
The onesim app shows what is left of your package and how fast you are getting through it, so an estimate is only ever a starting point. If you run low, a top-up takes about a minute and adds to the same eSIM.
Before you fly
Questions travellers ask.
Short answers about allowances, top-ups and what really counts against your data.
For most travellers, 3 to 5 GB covers a week of maps, messaging, a bit of browsing and some scrolling. If you stream video or make daily video calls, plan on 8 to 10 GB for the same week. The calculator above turns your own habits into a number.
It is if you keep to maps, messages and light browsing, and use Wi-Fi in the evenings. It is not if you watch video on mobile data — two weeks of an hour a night alone is more than 10 GB.
No. Only what goes over the mobile network counts against your package, so hotel and café Wi-Fi costs you nothing. Most travellers use far less than they expect for this reason.
Your data stops rather than continuing at a roaming rate, and you buy another package from the website or the app. It attaches to the same eSIM, so there is nothing to install again.
No. A package has an allowance and a validity period, and both end together — which is why buying a little tight and topping up often works out cheaper than buying big.
Yes, usually much more: bigger screens pull higher-quality video and desktop apps sync in the background. If you plan to tether a laptop, count it as an extra device in the calculator.