How can I increase the size of a .jpeg without losing quality?


Is it possible to make a .jpeg photo larger without losing "quality"?

I have a photo that is 450px x 750px and would like to make it 3 times bigger for web not print?

I've been told that Illustrator is the tool to make it happen and I have Illustrator CS6.

10/2/2013 4:30:00 PM

Accepted Answer

To say it short: No.

Images in jpg format are not vector based images. Vector based images can be resized without to lose quality. Bitmap images contains colored pixed. If you try to double the size one pixel has to grow to 4 pixel with the same color. Result: If you want the image 3 times bigger you will see the original pixels in your image.

It depends on your image if it is changeable to vector format or not. An usual photo (portrait of a human, mountains, landscape etc.) is not changeable to vector format.

10/2/2013 1:47:00 PM

As stated you cannot increase the size of a .jpeg without loosing quality but there is a margin of tolerance that you can increase the size of a .jpeg before it is noticeable.

Take my hero for instance (original file):

enter image description here

If I import this image into Photoshop and go to Image > Image Size (Shortcut Ctrl+Alt+I for PC or option/alt+cmd+I for Mac)

enter image description here

Change pixels to percent

enter image description here

You can change the percentage to 110% and repeat this till you receive a notable difference in quality. NOTE IF the image is high quality you can usually do an increase no more than 10 times from experience but as stated, this depends on the quality of the image you are adjusting.

enter image description here


enter image description here