How much data do you actually need?

The five numbers this is built on

There are only five figures worth knowing. Once you know them you never need a calculator again. Maps and turn by turn navigation cost about 5 MB an hour. That is not a typo.

A full week of navigating a foreign city, eight hours a day, is under 300 MB. People buy 20 GB because they are frightened of Google Maps. Google Maps is the cheapest thing on the phone.

Messaging and email together run about 10 MB a day. That holds whether you send twenty messages or two hundred, because text weighs nothing. Photos are the exception. One high resolution photo sent over a chat app is roughly 3 MB.

Social feeds with video autoplay cost about 300 MB an hour. This is the line that surprises people. An hour of scrolling on a train is 300 MB, and two hours a day for two weeks is 8.4 GB by itself. Turning autoplay off drops that hour to nearer 60 MB.

Video calling costs about 400 MB an hour on a phone, and more on a laptop because the camera resolution is higher. A daily standup of 30 minutes plus two client calls is around 1 GB a day before you look at anything else.

Streaming video is 1 to 3 GB an hour depending on quality. Standard definition on a phone screen sits near the bottom of that range. Anything the app labels high definition sits near the top. Set the mobile quality to standard and cap downloads to wifi.

Buy under, not over

Every other travel eSIM wants you to round up, and there is a reason. On a plan with a 30 day validity window, unused data is revenue. Industry estimates put the typical waste around a fifth of every plan sold.

Orbislo data does not expire, which flips the incentive. Buy the tier just under your estimate. If you get close, top up from the app in about ten seconds while standing in a queue. If you never get close, the remainder is waiting for you on the next trip.

That is also why the calculator recommends the tier at or below your figure rather than the one above it. We would make more money doing the opposite, and we are telling you not to.

The one case where headroom is worth paying for is a trip with no wifi at either end. A road trip through a country where hotels charge for internet is the clearest example. Everywhere else, buy under.

Three settings that cut the total before you buy anything

Ad and tracker blocking is already on by default on every Orbislo plan, which is where the quarter comes from in the table above. Saily bundles a comparable feature and had it audited at 28.6 percent saved, so this is not a number we invented.

It is applied after the activity totals rather than before, because it strips requests you never wanted rather than content you did.

1. Turn off video autoplay in every social app. An hour of feed drops from about 300 MB to about 60 MB. On a two week trip with two hours a day, that is 6.7 GB saved.
2. Set streaming apps to standard definition on mobile data and switch off automatic downloads. An hour of video drops from as much as 3 GB to nearer 1 GB.
3. On the laptop you tether, pause cloud backup and disable automatic operating system updates before you fly. A single system update over tethering can be 4 GB, and it will start itself.

When unlimited is the better buy

The crossover is around 1.3 GB a day. Below that the wallet wins, because 5 GB costs $10.89 and never expires. Above it, the unlimited day pass at $5.89 a day wins on price.

Unlimited runs at full 5G speed up to 2 GB a day before dropping to 1 Mbps for the rest of that day. We print both numbers, because 1 Mbps is honestly fine for maps, messaging and email, and honestly not fine for streaming.

For comparison, a week of unlimited costs about $27 at Airalo, $27.50 at Holafly and $28.99 at Saily. Airalo throttles near 3 GB a day. Holafly does not publish a fair use number at all, and was measured near 7 Mbps before throttling and under 1 Mbps after.