Microsoft Surface Battery Capacity

You might have a misunderstanding about battery capacity when it comes to different units. Most of the time, in mobile phones, power banks, mobile batteries mostly defined by mAh (milliamp-hours). For the Microsoft Surface family, it might have been noticed that the battery capacity is defined as mWh (milliwatts-hours).

In this tip, we will guide you on how to convert from mWh to mAh and vice-versa.

Table of contents

  1. Surface Battery Capacity
  2. How to Convert mWh to mAh?

1Surface Battery Capacity

Here is the list of the battery capacity of all Microsoft Surface is measured of both Wh and mAh:

Surface ModelWatt HoursMilliampere Hour, VoltsEst. Battery Life
Surface
Surface RT31.5 Wh4,257 mAh, 7.4 V8 hours
Surface Power Cover30.0 Wh4,054 mAh, 7.4 V-
Surface 231.5 Wh4,257 mAh, 7.4 V10 hours
Surface 327.5 Wh7,270 mAh, 3.78 V10 hours
Surface Go26.12 Wh3,411 mAh, 7.66V9 hours
Surface Go 226.81 Wh3500 mAh, 7.66V10 hours
Surface Go 326.81 Wh3500 mAh, 7.66V11 hours
Surface Pro
Surface Pro42.0 Wh5,676 mAh, 7.4 V-
Surface Pro 242.0 Wh5,676 mAh, 7.4 V-
Surface Pro 342.2 Wh5,547 mAh, 7.6 V9 hours
Surface Pro 438.2 Wh5,087 mAh, 7.5 V9 hours
Surface Pro 545.0 Wh5,940 mAh, 7.57 V13.5 hours
Surface Pro 645.0 Wh5,940 mAh, 7.57 V13.5 hours
Surface Pro 743.2 Wh5,702 mAh, 7.57 V10.5 hours
Surface Pro 7+50.4 Wh6,657 mAh, 7.57 V15 hours
Surface Pro 850.2 Wh-16 hours
Surface Pro 946.5 Wh-15.5 hours
Surface Pro 9 5G46.5 Wh-19 hours
Surface Pro X
Surface Pro X38.2 Wh5,039 mAh, 7.58 V13 hours
Surface Laptop
Surface Laptop45.2 Wh5,970 mAh, 7.57 V14.5 hours
Surface Laptop 245.2 Wh5,970 mAh, 7.57 V14.5 hours
Surface Laptop 3 13”45.8 Wh6,041 mAh, 7.58 V11.5 hours
Surface Laptop 3 15”45.8 Wh6,041 mAh, 7.58 V11.5 hours
Surface Laptop 4 13”45.8 Wh6,041 mAh, 7.58 V19 hours (AMD)
17 hours (Intel)
Surface Laptop 4 15”45.8 Wh6,041 mAh, 7.58 V17.5 hours (AMD)
16.5 hours (Intel)
Surface Laptop 5 13”45.8 Wh6,041 mAh, 7.58 V18 hours
Surface Laptop 5 15”45.8 Wh6,041 mAh, 7.58 V17 hours
Surface Laptop Go
Surface Laptop Go39.7 Wh5,235 mAh, 7.58 V13 hours
Surface Laptop Go241.0 Wh-13 hours
Surface Laptop SE
Surface Laptop SE35 Wh4,613 mAh, 7.6 V16 hours
Surface Laptop Studio
Surface Laptop Studio56.3 Wh-19 hours (i5)
18 hours (i7)
Surface Book
Surface Book69.0 Wh9,187 mAh, 7.5 V12 hours
— clipboard18.0 Wh2,387 mAh, 7.5 V3 hours
— base51.0 Wh6,800 mAh, 7.5 V9 hours
SB with Performance Base81.0 Wh10,787 mAh, 7.5 V16 hours
— clipboard18.0 Wh2,387 mAh, 7.5 V3 hours
— base63.0 Wh8,400 mAh, 7.5 V13 hours
Surface Book 2 13" i569.0 Wh9,187 mAh, 7.5 V17 hours
— clipboard18.0 Wh2,387 mAh, 7.5 V5 hours
— base51.0 Wh6,800 mAh, 7.5 V12 hours
Surface Book 2 13" i775.3 Wh10,027 mAh, 7.5 V17 hours
— clipboard18.0 Wh2,387 mAh, 7.5 V5 hours
— base57.3 Wh7,640 mAh, 7.5 V12 hours
Surface Book 2 15"90.0 Wh12,000 mAh, 7.5 V17 hours
— clipboard23.0 Wh3,066 mAh, 7.5 V5 hours
— base67.0 Wh8,933 mAh, 7.5 V12 hours
Surface Book 3 13" i569.0 Wh9,187 mAh, 7.5 V15.5 hours
Surface Book 3 13" i775.3 Wh10,027 mAh, 7.5 V15.5 hours
Surface Book 3 15"90.0 Wh12,000 mAh, 7.5 V17.5 hours

2How to Convert mWh to mAh?

In order to convert from mWh (milliwatt-hours) to mAh (milliamp-hours), we have a formula as below:

(mAh) = (mWh) / (V)

Example: Surface Pro 3 has a battery capacity of 42 Wh or 42,000 mWh has battery capacity in mAh as below:

42,000 mWh / 7.5 V = 5,600 mAh

So, the Surface Pro 3 has a battery capacity of 5,600 mAh.

You can also use the calculator below to help you convert from Wh to mAh or vice versa.

More Resources
Note Updated on October 2, 2021: We have updated this article to include the battery capacity of the new Surface Pro 8, Surface Laptop Studio, and Surface Go 3.