This article explains how to increase the resolution of an image using desktop GIMP 2.0 or later, macOS Preview (macOS 10.3 or later), and Image Size (iOS 9.0 or later).
Resolution relates to the number of pixels in a digital photo or image. The more pixels, the higher the resolution of the image. Key things to remember:
- To increase the resolution of an image : First, increase its size, then make sure it has optimal pixel density. The result is a larger image, but it may not look as clear as the original picture.
- Bigger doesn't mean sharper : the bigger the image, the more you'll see the 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 printing images.
To mitigate loss of clarity, follow these tips:
- Avoid significant increases in size : all images are different. When you increase the size by more than 30% or 40%, you may notice a loss of sharpness.
- If available, use a sharpening tool : GIMP and Photoshop include features to sharpen images. However, not all applications have these tools. The final effect may look unnatural, so use the sharpening tool sparingly to preserve a similar look to the original image.
GIMP is a free, open-source image editing tool available for Windows, macOS, and Linux. It provides extensive support for a variety of image formats, making it ideal for such tasks.
Here's how to increase image resolution using GIMP:
Open GIMP .
Select File > Open .
In the Open Image dialog box, select the image and choose Open .
Make sure the image window is the active window, then press Ctrl+A (Windows) or Command+A (Mac) to select the entire image.
Press Ctrl + C or Command + C to copy the image.
To create a higher-resolution copy, select File > New Opens the Create New Image dialog box.
To ensure that the final image has a resolution of 300 pixels per inch, select Advanced Options .
The pre-filled width and height match the current image. Do not change these values.
The dialog box expands to show the X and Y resolution of the image. The boxes may show canvas set to 300. If not, adjust the X and Y values to 300 and select OK .
You now have a new image window with the same dimensions as the original photo.
Select the new image's window and choose Image > Canvas Size .
Before adjusting the canvas width or height in the Set Image Canvas Size dialog box, make sure the chain icon to the right of the two measurements is locked.
Enter a new image width and press Tab . The height automatically adjusts to match the image proportions. This example goes from over 4000 pixels to 6000 pixels.
Be sure to remember or write down your new measurements. You will need these again later.
Select Resize .
In the new image window, press Ctrl + V or Command + V to paste the image.
Drag a corner of the image window (zoom out if necessary) to see all corners of the resized canvas.
You will find the original size image in the center of the new image window.
To make the pasted image completely cover the new canvas dimensions, go to the Layers dialog box and select Floating Selection (Paste Layer) if it's not already selected.
Go to the Toolbox dialog and select the Scale tool.
This tool may be located below the Cut tool.
Select the pasted image. In the Scale dialog box , make sure the chain icon is locked, and then enter the same width value you used in step 13.
You will see a preview of the adjusted image. If it looks good, select Zoom .
View the resampled image at its new dimensions.
Before exporting an image, check the quality of the image by zooming in. To do this, choose View > Zoom and select a zoom level.
When you are satisfied with the result, select Floating Selection (Paste Layer) > Anchor the layer icon to lock it to the background.
To export an image, select File > Export .
Select a location where you want to save the resized image and give it a name from the Export Image dialog box. Then select Export .
When naming an image, you can also set the file type by typing the extension. For example, name the image new_photo.png to save it as a PNG file, or name it new_photo.jpg to save it as a JPEG.
For best image quality, move the compression level slider to zero and select Export .
Preview is a useful tool for viewing photos and PDFs on Mac, and it includes some handy image editing tools.
Locate the image file, then right-click it and select Open with > Preview .
Select the marking toolbar icon.
Select the resize icon.
The icon may appear as three nested boxes.
Adjust the width to the desired amount and select OK . This example resizes the image from a width of 1000 pixels to 1300 pixels.
Make sure the Lock icon is off and select Resample Image .
Image resize. Select File > Save to overwrite the original image, or File > Export to save it as a new file.
Image Size for iOS is a photo editing tool that allows you to 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.
Install and open image size and select white frame (image picker).
Before selecting an image, grant the app access to the Photos app.
Select the image you want to resize from the image picker.
Select Select to open the image.
Select the chain icon to lock the width and height values.
Set your desired width value and select Done . This example scales the image to 6000 pixels. The height value is also automatically adjusted.
The photo is resampled to the new size. You can pinch and zoom to check the pixel quality.
Select the gear icon to see additional options. Make sure the Output Quality slider is at 100%.
If you plan to print the image, smooth out the pixelation. To do this, select the + (plus) icon to increase the print size correction factor , then select the back arrow to return to the home page.
To save the final image, select the Save arrow .
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 the image to be resampled.
Use apps like Photoshop, Picsart AI Photo Editor, or Photo & Picture Resizer to increase the resolution of images on Android. Depending on your model and operating system, you may be able to adjust the default resolution for taking photos from within your camera settings.
