eSIM guide
How much eSIM data do I need?
By Serhat Dogan · Founder & editor, Miyaw eSIM · Last updated 2026-06-07
Most travelers need about 1 GB for every 3–4 days of light use (maps, messaging, a little browsing), or roughly 1 GB per day if you scroll social media and stream. A one-week trip typically needs 3–5 GB; two weeks of heavy use, 10–20 GB. The tables below break it down by activity and trip length.
How much data per day?
| How you travel | Typical use per day | 1 GB lasts about |
|---|---|---|
| Light — maps, messaging, the odd web search | 0.2–0.4 GB | 3–4 days |
| Medium — the above plus social feeds and music | 0.5–1 GB | 1–2 days |
| Heavy — the above plus video calls and streaming | 1.5–3 GB | Under a day |
How much data does each activity use?
Not all screen time costs the same. Maps and messaging are tiny; video is what drains an allowance. These are typical per-hour estimates — your real usage depends on quality settings, autoplay, and how often the app refreshes.
| Activity | Data per hour | Notes |
|---|---|---|
| Maps & navigation | 5–15 MB | Mostly cached; download offline maps to use even less |
| Messaging (text, photos) | 5–20 MB | WhatsApp/iMessage text is negligible; photos add up |
| Web, email, search | 10–50 MB | Image-heavy pages cost more |
| Music streaming | 40–150 MB | Lower the quality on the road to save data |
| Social feeds (Instagram, TikTok, X) | 150–500 MB | Autoplay video is the hidden cost |
| Video calls (FaceTime, WhatsApp, Zoom) | 200–600 MB | Audio-only calls use a fraction of this |
| Video streaming (YouTube, Netflix) | 0.5–3 GB | SD is ~0.5–1 GB/hr; HD can hit 3 GB/hr |
Using your phone as a hotspot doesn't have its own rate — it costs whatever the connected laptop or tablet is doing, which is usually web and video.
How much eSIM data for a 1-week or 2-week trip?
Pick the row that matches how you actually travel, then add roughly 20% as a buffer for unexpected days. It's cheaper to top up than to be stuck offline — but most people overestimate.
| How you travel | 1 week | 2 weeks |
|---|---|---|
| Light | ~3 GB | ~5 GB |
| Medium | ~5 GB | ~10 GB |
| Heavy / hotspot | 10–15 GB | 20 GB+ or unlimited |
What actually uses the most data abroad?
If you remember one thing: video is expensive, everything else is cheap. An hour of HD video streaming can use more data than a whole day of maps, messaging and browsing combined. Social-media feeds count as video too, because Reels, TikTok and autoplay clips stream constantly while you scroll.
Maps are the surprise — Google Maps and Apple Maps cache the route, so a full day of navigation often uses less than 50 MB. Download the offline map of your city before you fly and it drops close to zero.
Does the country change how much you need?
The amount of data you consume is the same anywhere — an HD video is an HD video in Tokyo or Toledo. What changes is speed. Faster networks make it easier to burn through data without noticing, because nothing buffers. In our country speed dataset (OpenSignal, 2025–2026), South Korea's median 5G runs about 430 Mbps and Japan's about 161 Mbps, while many networks sit between 100 and 280 Mbps.
So the country doesn't raise your GB needs directly — but a fast 5G connection plus generous Wi-Fi at the hotel can pull your usage in opposite directions. Plan for your habits, not the network. Each Miyaw country page lists that destination's real 4G/5G speeds so you can sanity-check.
How much eSIM data do I need in Japan?
Japan is the single most-asked destination, so here's a worked example. A typical week in Japan — maps to find ramen shops and train platforms, messaging, social media, a few video calls home — lands squarely in the "medium" profile: about 0.7 GB a day, so roughly 5 GB for the week.
If you'll livestream, hotspot a laptop, or video-call daily, step up to 10 GB or an unlimited plan. If you mostly use hotel and café Wi-Fi and just need maps and messaging out and about, 3 GB is plenty. Japan also has fast, widely available 5G, so streaming won't feel limited — which is exactly why it's easy to use more than you planned.
Is an "unlimited" plan worth it?
"Unlimited" almost never means infinite full-speed data. Nearly every unlimited travel eSIM has a fair-use policy: after a daily high-speed cap (often somewhere around 1–2 GB), your speed is throttled for the rest of the day. That's fine for messaging and maps, but slow for video.
For most travelers a fixed-GB plan is cheaper and more honest — you can see exactly what you're buying. Unlimited makes sense if you genuinely stream or hotspot every day and don't want to think about it. We compare real plans, including from-prices against Airalo, Saily, Nomad and Holafly, on our best-eSIM pages.
What if you run out?
Running low isn't a crisis. With Miyaw you can buy another plan or top up the same eSIM in a minute without removing or re-scanning anything — your number and setup stay put. Turn on data-usage warnings in your phone settings so you see it coming, and keep that ~20% buffer when you choose a plan.
How much data — quick answers
- How much is 1 GB of data?
- Roughly: 1 GB is about 8–10 hours of maps, or 3–4 hours of scrolling social media, or around an hour of HD video. A light traveler can stretch 1 GB across 3–4 days.
- Is 5 GB enough for a week?
- For most travelers — maps, messaging, social media and the odd video call — yes. That's about 0.7 GB a day. Add more if you stream video daily or use your phone as a hotspot.
- What uses the most data when travelling?
- Video streaming and video calls by far, followed by social-media feeds with autoplay video. Maps, messaging and email use very little.
- Can I add more data if I run out?
- Yes. With Miyaw you can buy another plan or top up the same eSIM in about a minute — no need to remove the eSIM or change any settings.