Computers & Laptops

Monthly Data Usage Calculator

Daily, weekly and monthly data from several activities, over whatever number of days your billing month has.

43 inputs Free, no sign-up

Your figures

Name each activity and enter what it uses per hour on your own connection.

A billing month is 28, 30 or 31 days. Use 31 for the worst case.

Optional.

Try an example

Result

Your result

Enter your figures and the result appears here.

Estimates only. Rates, fees and specifications change. Confirm against the official source before you rely on a figure — see our disclaimer.

About this calculator

A monthly allowance is spent a day at a time. Listing what each activity costs per hour and multiplying out is the only way to see which one is doing the damage.

Every consumption figure here is yours. There is no table of what any service uses, because that would be a guess dressed up as data.

How to use this calculator

  1. List each activity with what it uses per hour, the hours a day and how many devices.
  2. Set the number of days in your billing period - 31 for the worst case.
  3. Add your allowance to see how much of it the list accounts for.

The formula

A day   = sum of (data per hour x hours a day x devices)
A week  = A day x 7
A month = A day x Days in the period
SymbolMeaningUnit
Data an hour What each activity uses GB or MB
Days Days in the period

Worked example

Three activities over a 31-day month:

Video       3 GB/h x 2 h       = 6 GB a day
Calls       0.9 GB/h x 1 h      = 0.9 GB a day
Browsing    0.3 GB/h x 4 h      = 1.2 GB a day
A day                            = 8.1 GB
A month     8.1 x 31             = 251.1 GB

Notes and limits

  • Sorting the result by size shows immediately which activity dominates. It is almost always video.
  • Background traffic is not here unless you add a row for it, and on a household connection it is routinely tens of gigabytes a month.
  • A billing month of 31 days uses 10% more than one of 28. If you are close to an allowance, use the longer figure.
  • Providers count in decimal gigabytes; your devices count in binary. The two will not agree exactly and neither is wrong.

What this calculation assumes

  • Every consumption figure is one you entered.
  • Background traffic is excluded unless you add a row for it.
  • A week is seven days; a month is the number of days you set.

Frequently asked questions

How do I work out my monthly data usage?

List each activity with what it uses per hour and how long it runs, add them for a daily total, and multiply by the days in your billing month. The per-hour figures have to come from your own apps.

How many days should I use?

The number in your billing period. Thirty-one is the worst case, and if the total is close to your allowance that is the one to plan against.

My calculated total is lower than my bill says. Why?

Background traffic almost certainly - updates, cloud sync, backups and devices not on the list. Add a row with the difference in it and you will see how large it is.

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