Start with how you actually use your phone
The honest answer to "how much data do I need travelling" is: less than you think, unless you stream. Most travellers overbuy because they picture heavy home use, then spend the trip walking around, sightseeing and sleeping. Your phone only burns data when the screen is on and something is loading. So the smart way to size a plan is to work out your daily habits, multiply by the number of days, and add a small buffer.
Below are realistic daily estimates for the things travellers do most. Figures are approximate and vary by app, video quality and how chatty you are, but they are close enough to plan with confidence.
What common activities actually cost
- Maps and navigation: roughly 5 to 20 MB per day if you look things up as you go. Turn-by-turn driving for hours uses more, but pinning a destination and glancing at it uses very little.
- Messaging (WhatsApp, iMessage, texts): around 5 to 20 MB per day for text and the odd photo. Voice notes and picture-heavy group chats push this higher.
- Email and general browsing: about 20 to 50 MB per day for checking messages, reading and light web use.
- Social media scrolling: roughly 100 to 250 MB per hour. Feeds autoplay video, which is the hidden cost. Posting Stories and Reels adds up fast.
- Music streaming: around 40 to 100 MB per hour depending on quality.
- Video streaming and calls: the big one. Standard definition video is roughly 0.5 to 1 GB per hour, HD around 1.5 to 3 GB per hour. Video calls sit near 0.5 to 1.5 GB per hour.
Light, typical and heavy: daily estimates
Group yourself into one of three profiles. This is the fastest way to answer the question honestly.
- Light user, about 200 to 400 MB a day: maps to get around, messaging to stay in touch, a quick check of email and a little browsing. No streaming on mobile data. This is the classic sightseeing traveller.
- Typical user, about 500 MB to 1 GB a day: everything above plus regular social scrolling, uploading photos, some music and the occasional short video. This covers most people.
- Heavy user, about 1.5 to 3 GB a day or more: frequent video streaming, long video calls home, lots of Reels and Stories, or tethering a laptop for work. If you watch anything on the move, you are here.
The simple days x GB formula
Once you know your daily profile, buying is easy: multiply your daily estimate by the number of days, then round up for a buffer.
- A weekend (3 days), typical use: 3 x roughly 0.7 GB is about 2 GB. A 3 to 5 GB plan is comfortable.
- A week (7 days), typical use: 7 x roughly 0.7 GB is about 5 GB. A 5 to 10 GB plan gives headroom.
- Two weeks (14 days), light use: 14 x roughly 0.3 GB is about 4 GB. A 5 GB plan works if you lean on Wi-Fi.
- Two weeks (14 days), heavy use: 14 x 2 GB is about 28 GB. Look at a large bundle or an unlimited-style plan where available.
A sensible rule: add 20 to 30 percent on top of your estimate. Running a little over is far more annoying than a small unused margin, and topping up mid-trip is quick if you do need more.
How Wi-Fi changes the maths
Wi-Fi is the single biggest lever on how much data you buy. Hotels, cafes, airports, museums and many restaurants offer it, and the heaviest tasks are exactly the ones you can shift onto it.
- Download offline maps, playlists, podcasts and any shows before you leave your accommodation each morning.
- Save video calls home, big photo and video backups, and app updates for the evening on hotel Wi-Fi.
- Set your phone to update apps and back up photos on Wi-Fi only, so nothing large runs silently on your plan.
Do this and even a heavy user often drops into the typical range, because mobile data ends up handling only maps, messaging and light browsing while you are out. A traveller who sleeps and eats on Wi-Fi and only needs data between venues can genuinely get through a week on a few GB.
A quick note on how Simju plans work
With a Simju eSIM your data is delivered instantly by email as a QR code the moment you pay, and the plan only starts counting when you first connect at your destination, so buying a few days early costs you nothing. Plans are data-only with hotspot sharing, so you can tether a laptop or a travel companion's phone from your allowance. Your physical SIM and number stay active for calls, WhatsApp and iMessage. If you are torn between two sizes, our coverage pages and help centre show what is available per destination, and 24/7 support can point you to the right bundle.
Still unsure? Start slightly smaller than you fear, keep the heavy stuff on Wi-Fi, and top up only if you need to. Browse plans for 190+ destinations on our full eSIM range, or read how it works before you travel.