What the Mobile Data Usage Calculator does
This calculator estimates how many gigabytes a month your phone habits actually need. Put hours a week against the things you do - video, calls, music, social, browsing, navigation - and it multiplies each by a data rate, adds them up, compares the total with your allowance, and works out the daily budget and the day the allowance runs out at your current pace.
The rates matter more than the arithmetic, so they are stated openly. Video, music and call rates come from Netflix, YouTube, Spotify and Zoom's own published figures, either as published or converted from a published bitrate, and each one is labelled with which. Social scrolling, general browsing, gaming and maps have no official figure from anybody, so those are marked as estimates for you to replace. Every rate is editable, and everything runs in your browser.
How to use it
- Enter hours a week for each activity you actually do - it is fine to leave most of the list empty. Photo backups and app updates are counted per item rather than per hour.
- Adjust any rate that does not match you. A phone set to 480p video uses a fifth of what 1080p does, and the default for social scrolling is only a working assumption.
- Enter your allowance and the number of days in the billing period. Leave the allowance blank if the plan is unlimited and you only want the estimate.
- For a mid-month check, add how much you have used so far and which day of the period it is. The calculator shows your pace, the projected total and the day the allowance runs out.
- Read the breakdown to see which single activity is responsible for most of it - it is nearly always video - and use the CSV or the copied summary if you are comparing plans.
Reading the results
The headline figure is decimal gigabytes, the unit plans are sold in: 1 GB = 1,000,000,000 bytes. The GiB figure next to it is the same traffic in the binary units phones often display, which is why a 30 GB bundle can read as 27.9 GB on the handset.
The daily budget is simply the allowance divided by the billing period. The safe daily figure that appears once you enter a mid-month reading is different: it is what is left divided by the days remaining, which is the number to pay attention to.
Rate basis tells you how much to trust each line. "Published" came from the provider's own help page, "derived" was converted from a bitrate they publish, and "estimate" means nobody publishes a figure and this one is a working assumption.
The projection assumes the rest of the month looks like the part you have measured. A holiday, a long train journey or a week without Wi-Fi at home will break it.
Worked example: a commuter on a 20 GB plan
Forty minutes each way on the train, five days a week: about five hours a week of YouTube at 720p. YouTube's recommended sustained speed for 720p is 2.5 Mbps, and 2.5 x 3600 / 8000 = 1.125 GB per hour. Over a 30-day month that is 5 x 30/7 = 21.4 hours, so 24.1 GB.
Six hours a week of Spotify at its Very High setting - about 320 kbit/s, or 0.144 GB per hour - adds 3.7 GB. Five hours a week of social scrolling at the working assumption of 0.8 GB per hour adds 17.1 GB, and that single uncertain figure is the second largest item on the list.
Browsing, maps and photo backups add roughly 1.4 GB. The month comes to about 46 GB, which is more than twice a 20 GB allowance - and the fix is visible in the breakdown rather than in a guess: dropping YouTube to 480p (0.495 GB per hour) saves 13.5 GB, and downloading playlists on Wi-Fi removes the music entirely.
Because two of the four big lines are unpublished estimates, the page says so rather than presenting 46 GB as a measurement.
Formulas and scoring rules
- Data for one activity
gb = hours_per_week x (period_days / 7) x gb_per_hourPer-item activities use count x gb_per_item instead.- Bitrate to data rate
gb_per_hour = Mbps x 3600 / 8000A sustained 5 Mbps stream is 2.25 GB per hour. Two-way traffic such as a video call counts both directions.- Decimal and binary gigabytes
GiB = GB x 1,000,000,000 / 1,073,741,824IEC 80000-13 names the binary units. 30 GB is 27.94 GiB.- Daily budget
daily_budget = allowance / period_days- Pace and projection
pace = used / day_of_period; projected = pace x period_days- Run-out day
run_out_day = day + (allowance - used) / paceNull when that lands beyond the end of the period.- Safe daily rate for the rest of the period
safe_daily = (allowance - used) / (period_days - day)
Video is the whole question
Every other activity is rounding error next to video. Netflix publishes up to 0.3 GB an hour on its lowest setting, 0.7 on medium, 3 in high definition and 7 in 4K - a factor of more than twenty between the ends of that range, all for the same programme. One evening of 4K on mobile data can use more than a month of music, browsing and messaging combined.
That is also where the easy savings are. Capping streaming quality on mobile, downloading over Wi-Fi before you travel, and turning off autoplay in social apps usually move an estimate more than changing plan does. The breakdown here is meant to show which lever is worth pulling before you pay for more gigabytes.
Why the honest answer includes an error bar
Providers publish rates for their own services, and those are reliable. Nobody publishes a data-per-hour figure for scrolling a social feed, because it depends entirely on how much video autoplays, at what resolution, and how long you linger - the same hour can be 0.2 GB or 2 GB.
Rather than invent a number and present it as fact, this tool marks those rates as estimates, shows what proportion of your total depends on them, and points you at the measurement you already have: both Android and iOS report mobile data per app for the current period. Replacing two or three estimates with your own figures turns a rough estimate into a good one.
Limitations: what the result does not prove
- It is an estimate built from rates and hours, not a measurement of your phone. Only your phone's own mobile-data screen or your operator's records can tell you what you really used.
- Rates for social media, browsing, gaming and navigation are working assumptions, not published figures, and they are labelled as such. Anything resting on them carries that uncertainty.
- The figures in the rate file were read from the providers' pages on the review date shown on the page. Providers change their encoding and their documentation; nothing here is live.
- Tethering, background updates, cloud sync, automatic photo and video backup and operating-system updates can dwarf everything you plan for. Add them as items if they run over mobile data.
- Zero-rated data, carrier video-quality caps, roaming policies and fair-use throttling all change what an allowance means in practice. Read your plan's terms; the arithmetic here does not know about them.
Privacy: where your data goes
Everything you paste, type or drop is processed in this browser tab. It is not uploaded, logged, stored or sent to analytics. Session recording and tag-manager scripts are switched off on this page.
Standards and sources
- IEC 80000-13 - Information science and technology quantities (KiB, MiB) - checked 19 Sep 2026
- Netflix Help Centre - how to control how much data Netflix uses
- YouTube Help - system requirements and recommended speeds
- Spotify Support - audio quality and bitrates
- Zoom Support - system requirements and bandwidth
Frequently asked questions
How much data does an hour of streaming video use?
It depends almost entirely on quality. Netflix publishes up to 0.3 GB an hour on its data-saver setting, 0.7 on medium, about 3 GB in HD and up to 7 GB in 4K. YouTube publishes recommended speeds instead: 1.1 Mbps at 480p and 5 Mbps at 1080p, which work out at roughly 0.5 and 2.25 GB an hour.
How many GB do I need a month?
Add up the hours you actually spend on each activity and multiply by its rate - which is what this page does. As a rough shape, a light user with music and messaging can live on 3-5 GB, a commuter who streams video on the train needs tens of gigabytes, and anyone doing video calls on mobile data should budget about 1 to 2 GB an hour of call.
Why does my phone show less data than my plan says I have?
Because they are different units. Plans are sold in decimal gigabytes (1,000,000,000 bytes) while phones often report binary gibibytes (1,073,741,824 bytes), which IEC 80000-13 calls GiB. A 30 GB bundle is 27.94 GiB, so nothing has gone missing - the page shows both.
How much data does a video call use?
Zoom recommends 1.2 Mbps in each direction for 720p one-to-one, and a call uses both, so about 1.08 GB an hour. A 720p group call at its recommended 2.6 up and 1.8 down works out near 2 GB an hour. Audio-only calls are a fraction of that, under 0.1 GB an hour.
Does downloading use less data than streaming?
Downloading the same thing once uses about the same data as streaming it once, and less if you watch it more than once. The real saving is doing the download on Wi-Fi: offline playlists, downloaded episodes and offline maps then cost nothing from the mobile allowance.
How accurate is this estimate?
As accurate as the rates and the hours you give it. Video, music and call rates come from the providers themselves; social, browsing, gaming and maps are working assumptions and are flagged, with the proportion of your total that depends on them shown. Replace those with the per-app figures from your phone settings and the estimate becomes genuinely good.
When will my data run out this month?
Enter what you have used and which day of the billing period it is. The page divides one by the other to get your daily pace, projects it to the end of the period, and names the day the allowance would run out - plus the daily rate that would keep you inside it instead.
Is anything about my usage sent anywhere?
No. The page loads one small file of default rates from this site and does everything else in your browser. The hours you enter, your allowance and your usage are never transmitted or stored, and the CSV is generated locally.
Last reviewed by the A2Z.Tools team against the sources listed above.
