title- What Size Are Smartphone Photos

What Size Are Smartphone Photos?

When taking pictures with our phones, most of us don’t even think about the actual size of the photos we’re taking. That is until the phone warns us we’re running out of memory. Only then we worry about how much space our photos occupy.

How big are mobile photos? The size of a photo depends on many factors but mainly the sensor and number of megapixels it has.

The more megapixels, the larger the resolution and, ultimately, the larger you can print the image in photo quality. More resolution also means a bigger file size.

However, two images with the same resolution can have different file sizes depending on the format and contents of the picture.

What affects the file size of smartphone photos?

Unless it’s the exact same shot, no two images captured by the same camera are ever the same file size. This could be because of the contents of the photograph or the settings of the camera.

At the very core of what affects the size of mobile photos is the design and specs of the camera, particularly the sensor and the number of megapixels on it.

1. Megapixels

The term ‘megapixels’ refers to one million pixels. These pixels are individual squares that make up an image.

For example, a 12MP image is made up of 12 million pixels. The higher the megapixel count, the more detailed the image is. This not only means a bigger file size, but also a larger physical print. More on this later.

Here’s basically what this means: A 12MP image has a resolution of about 4000 x 3000 pixels in width and height. This would give you a photo-quality print of approximately 13"x10” and an approximate jpeg file size of ~3MB.

Continue reading below to find how I got to those figures.

2. The sensor

Megapixels aren’t the “be-all and end-all” of the factors that affect file size. The size of the sensor also plays a part because it determines how many pixels the sensor can accommodate, and how big the pixels can be.

A big sensor with large pixels can receive a lot more light information than a small sensor with tiny pixels. All that information captured by the sensor means more space will be required.

3. The detail

The amount of detail that is in the picture adds to the overall file size. If you take a photo in a low-light environment or against nothing but a solid colour, there isn’t much light information or colour variation in the shot. So, the resulting file size will be small.

a photo with lots of colour info versus a dark photo with very little colour

On the other hand, bright pictures with a lot of colour and intricate detail will definitely yield larger file sizes. This is because there’s a lot more light information of varying intensities coming through that needs to be processed.

4. The file format

Not all smartphones have support for more than one file format for photos other than jpeg. However, some phones give you an option to either shoot jpeg or RAW. If you choose to shoot RAW, then the file size of your photos will be significantly larger.

raw versus jpeg

Jpeg vs RAW file size

These two file formats have their own distinct qualities that affect the file size (not resolution).

As previously mentioned, jpeg is the most popular format that is used in pretty much every camera phone on the market. When your smartphone is set to save in jpeg (or jpg) format, the image is automatically processed and compressed to an optimum size and tosses out any extra data. The result is a very decent, optimised, high-quality picture with a small file size.

RAW (DNG) files are as the name suggests raw. These type of files are quite large and bulky because, unlike with jpeg, they aren’t automatically processed. Therefore, they remain uncompressed and retain all the picture data that a jpeg file would’ve otherwise stripped away. This allows for more flexibility in post-processing.

Because it is uncompressed and unprocessed, a RAW file can be roughly three times or more the size of a jpeg. For example, if an average photo taken with a 12MP smartphone camera is ~3MB (megabytes) in jpeg format, it is possible that the same picture in RAW format could be as large as ~19MB.

The folks at Toolstud.io have a very handy megapixel calculator you can use to give you a rough idea of how large in megabytes (MB) a photo can be given its resolution from calculating its megapixels (MP) and file format.


Is there a way to reduce the MB size of a photo without losing quality?

An easy way to quickly and easily reduce the file size or even resolution of a picture is to use a third-party app like Photo & Picture Resizer for Android.

This app allows you to easily reduce photo size without any apparent loss of quality. You can use it before uploading your images online or sending loved ones your photos via email or text. It’s convenient and super simple to use.

Desqueeze available on iPhone does pretty much the same function. Not only does it easily resize photos, but it also does the same for videos as well.

It can output images in a variety of formats for both photos and videos without a hassle. What’s more, it allows batch resizing, which I think is pretty cool.

If your pictures are on your computer and you would like to resize them from there, a quick Google search for online picture resizing will give you endless options of sites where you can upload your picture and have it automatically resized or enter your own specifications. ResizeImage is a good example of such a site.

Messenger apps such as WhatsApp and email clients like Gmail are known to compress images that are sent via their platform.

The loss of quality on the resized photo is not so apparent on the phone screen but you won’t get as large a print from it as you would have from the original photo.

How large can you print your photos?

Many factors influence how large you can print your smartphone photos but the main one is the actual resolution of the photos. The higher the resolution, the larger the print.

To find what size you can print a photo, you need to divide each dimension of the resolution by the PPI (pixel per inch) quality you wish to print. 300ppi gives you photo-quality prints while 200ppi can still give you good quality.

Anything 150 and below is low quality and may make the pixels visible when looking at the images.

For example, a smartphone with a 12MP resolution camera will produce a print of 14” x 9” at 300ppi, 21” x 14” at 200ppi, and 26” x 16” at 150ppi.

table showing the size of photos you can print
megapixel size compared to paper size

Photo print size with paper size comparison

Keep in mind that as much as printing at 150ppi allows you to print larger pictures, the photos aren’t as sharp as they would be if they were printed smaller at 300ppi.

It’s important to understand PPI (pixels per inch) and not confuse it with DPI (dots per inch), especially if you’re looking to print your own photos from home.

It’s worth noting that cropping and editing your photos with some third-party apps such as Instagram may affect the size and resolution of your photo.

I recommend using pro-level apps and software to shoot and edit your photos and retain their original size.

So, does size matter? I’d say it does, depending on your needs. If you’re a serious smartphone photographer who sells prints of their work, then you’d probably want to shoot RAW at a higher resolution. If that’s the case, expect large file sizes.

But if you’re the average Joe then you don’t really need to shoot RAW. You don’t even need to shoot at a high resolution. An 8MP. jpeg is more than enough to post on social media or text to friends and family.

And at an estimated file size of about 2MB, you will have even more space on your device.

free ebook download link

For useful tips on how to capture great photos with your phone, check out the 15 Tips on How To Take Amazing Photos With Your Phone.

If you want to learn more about how to improve your smartphone photography, download the 5 Ways To Improve Your Smartphone Photography ebook here. There’s a lot to learn in its 22 pages of content and it’s ABSOLUTELY FREE!!!

Comments 3

  1. Great post!
    I recently wrote an article about the size of photos on a smartphone. Not so much about the size of photos a smartphone can take, but more on how smartphones and also the network providers tend to reduce the size of the original photo which is downloaded onto the phone. This is to save space as sometimes storage is on smartphones is limited. Saving data can also be the reason photos are reduced on smartphones as not everybody is on an “unlimited data deal”. For example when you receive a whatsapp image, the photo is not the same size as on the person who took the image, it has been reduced. People who don’t realise this often end up having problems when trying to have photos printed. For an insight into the problems that people have had, trying to get decent print images, check out my article here: https://www.photorestorationretouching.com/why-are-cell-phone-photos-so-small/
    Thanks for such an informative post, I will certainly share it!

    1. Post

      Hi Chris. Thanks for your comment 🙂 It’s true that some apps like WhatsApp reduce the size of mobile images for the sake of saving data. Editing apps such as Instagram also save a reduced version of the image once you’re done editing it. That’s why I always recommend using pro-level editing apps such as Snapseed and Lightroom Mobile because they retain the original size of the photo when you’re done editing instead of reducing their size. That makes it much better for printing

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