How to Make High-Resolution Images

This article explains how to increase the resolution of an image using desktop GIMP 2.0, macOS Preview (macOS 10.3 or later), and Image Size (iOS 9.0 or later).

Tips for Increasing Image Resolution

Resolution correlates to the number of pixels in a digital photograph or image. The more pixels there are, the higher the image’s resolution.

To improve a picture’s resolution, increase its size, then make sure it has the optimal pixel density. The result is a larger image, but it may look less sharp than the original picture. The bigger you make an image, the more you’ll see a difference in sharpness. This process makes the picture larger and adds pixels, not more detail.

As a rule of thumb, 300 pixels-per-inch is the accepted standard for printed images.

To mitigate the loss of sharpness, follow these tips:

• Avoid a significant increase in size: All images are different. When you increase the dimensions by more than 30 percent or 40 percent, you’ll likely notice a loss of sharpness.
• Use sharpen tools when available: GIMP and Photoshop include features for sharpening images. However, not all apps have these tools. The final effect can seem unnatural, so use sharpen tools sparingly to retain a similar look to the original picture.

How to Make High-Resolution Images Using GIMP

GIMP is a free, open-source image editing tool available for Windows, macOS, and Linux. It offers broad support for a host of image formats, making it ideal for this kind of task.

Here’s how to improve image resolution with GIMP:

1. Open GIMP.

2. Select File > Open.

   
   

3. In the Open Image dialog box, choose the image and select Open.

   
   

4. Make sure the image window is the active window.

5. Press Ctrl+A (Windows) or Command+A (Mac) to select the whole image.

6. Press Ctrl+C or Command+C to copy the image.

7. To create a higher resolution copy, select File > New to open the Create a New Image dialog box.

   
   

8. To ensure the final picture has a resolution of 300 pixels per inch, select Advanced Options.

   
   

   The pre-filled width and height match the current image. Don’t change these values.

9. The dialog box expands, revealing the X and Y resolutions for the image. The boxes may show the canvas is set to 300. If not, adjust the X and Y values to 300, then select OK.

   
   

10. You now have a new image window with the same dimensions as the original photo.

11. Select the window for the new image, then select Image > Canvas Size.

    
    

12. The Set Image Canvas Size dialog box opens, where you’ll adjust the canvas size.

13. Before adjusting the canvas width or height, make sure that the chain icon to the right of both measurements is locked.

    
    

14. Enter the new image width, then press Tab. The height automatically adjusts to match the image scale. This example goes from just over 4000 pixels to 6000 pixels.

    Be sure to remember or jot down your new dimensions. You’ll need these again later.

15. Select Resize.

    
    

16. In the new image window, press Ctrl+V or Command+V to paste the image.

    
    

17. Drag the corner of the image window (and zoom out if necessary) to see all corners of the resized canvas. The image is pasted in the center of the new image window at its original size.

    
    

18. To make the pasted image fully cover the new canvas size, go to the Layers dialog and select Floating Selection (Pasted Layer) if it isn’t selected.

    
    

19. Go to the Toolbox dialog and select the Scale tool.

    
    

20. Select the pasted image. A scale guide and the Scale dialog box appear. In the Scale dialog box, ensure the chain icon is locked, then enter the same width value you used in step 13.

    
    

21. You’ll see a preview of what the resized image will look like. If it looks good, select Scale.

    
    

22. The image is resampled at the newer size.

    
    

23. Before exporting the image, check the quality of it by zooming in. To do this, select View > Zoom, then choose a zoom level.

    
    

24. When you’re happy with the result, go to the Layers dialog, right-click Floating Selection (Pasted Layer), then select Anchor Layer to lock it to the background.

    
    

25. To export your image, select File > Export.

    
    

26. The Export Image dialog box will open. Choose where you want to save the resized image and name it. Then select Export.

    
    

    When naming an image, you can also set the file type by typing the extension. For example, call the image new_photo.png to save it as a PNG file, or name it new_photo.jpg to save it as a JPEG.

27. The Export Image as dialog box appears, offering settings for the saved photo. To get the best image quality, move the Compression Level slider to zero, then select Export.

    
    

How to Increase Image Resolution Using macOS Preview

Preview is a valuable tool for viewing photos and PDFs on your Mac, and it includes some handy image editing tools.

1. Locate the image file, then right-click it and select Open with > Preview.

   
   

2. Select the Markup Toolbar icon.

   
   

3. Select the Adjust Size icon.

   
   

4. Adjust the width to the desired amount, then select OK. This example resizes a picture from a width of 1000 pixels to 1300 pixels.

   
   

   Ensure the lock icon is closed and Resample Image is selected.

5. The image resizes. Select File > Save to overwrite the original image or File > Export to save it as a new file.

   
   

How to Increase Resolution Using Image Size for iPhone

Image Size for iOS is a photo editing tool that lets you resize images. It’s free, but you can choose to pay if you want to remove ads. Download Image Size for iOS from the App Store.

1. Install and open Image Size.

2. Tap the main white box. Select OK to grant the app access to your photos, then select the white box once more to open the image picker.

3. Select the image you want to resize.

   
   

4. Select Choose to open the image.

5. Select the chain icon to lock the Width and Height values.

6. Set your desired Width value, then select Done. This example scales the image up to 6000 pixels. The Height value automatically adjusts as well.

   
   

7. The photo resamples at the new size. You can pinch and zoom to check the pixel quality.

8. Select the gear icon to view additional options. Ensure the Output Quality slider is at 100 percent.

   
   

9. If you intend to print the image, smooth out the pixelation. To do this, select the + icon to increase the Print size correction factor, then select the back arrow to return to the main page.

10. To save the final image, select the save arrow.

    
    

FAQ

• How do I increase image resolution in Photoshop?

  Open the image in Photoshop and select Image › Image Size. From there, you can adjust the Resolution, change the width and height, and choose whether you want to resample the image.

• How do I increase the resolution of an image on my Android phone?

  Use an app like Photoshop, AI Photo Enhancer, or Photo Resizer to increase the resolution of an image on Android. To adjust the default resolution for pictures you take, go to the Settings in the Camera app,