To compress jpeg in photoshop or GIMP, adjust the quality slider, strip metadata, and choose encoding like progressive or subsampling. Both editors preview the resulting file size. You can balance visual detail against kilobytes before you save.
Compressing a JPEG in Photoshop
Photoshop gives you two ways to save a JPEG with manual compression controls. The most useful is File > Export > Save for Web (Legacy). It offers fine control over quality and metadata. The shortcut is Alt+Shift+Ctrl+S on Windows or Option+Shift+Cmd+S on Mac.
In the Save for Web dialog, set JPEG quality from 0 to 100. A lower number means more compression and a smaller file. The dialog shows the resulting file size as you move the slider. You see the effect immediately.
Optimized and Progressive
Two checkboxes matter: Optimized and Progressive. Optimized creates a slightly smaller file through Huffman optimization. Progressive makes the image load in multiple passes in older browsers, but it increases file size slightly. Leave Optimized checked and Progressive unchecked for most uses.
Metadata Menu
The Metadata menu lets you choose what information to include. Setting it to None removes all EXIF data, copyright info, and camera settings. That reduces file size.
Another method is File > Save a Copy as JPEG. It uses a quality scale from 0 to 12, less precise than the 0-100 range in Save for Web. The Save a Copy dialog does not show a file size preview, so check the file after saving.
Photoshop Save for Web Options
Quality Slider (0-100)
Move the quality slider to the left for smaller files. A value in the middle range produces a good balance between size and visual detail. The dialog updates the estimated file size in real time.
Optimized and Progressive
Check Optimized for a smaller file. Leave Progressive unchecked unless you need the image to appear gradually in old browsers. Progressive adds a small amount to the file size.
Metadata Menu
Open the Metadata dropdown and choose None to strip all embedded data. This removes camera settings, GPS coordinates, and any captions you added.
Compressing a JPEG in GIMP
In GIMP, use File > Export As (shortcut Shift+Ctrl+E). Name the file with a .jpg extension. GIMP opens a JPEG export dialog with a Quality slider from 0 to 100.
The dialog includes a Show preview in image window checkbox. When checked, the image window updates to show how the compressed version will look. The dialog displays the resulting file size. Adjust quality and see the exact file size before saving.
Advanced Options
Click the arrow to expand Advanced Options. Here you can set:
- Optimize, produces a smaller file by using Huffman tables.
- Progressive, creates a progressive JPEG that loads in multiple scans.
- Subsampling, choose between 4:4:4 (no color reduction), 4:2:2 (half color resolution horizontally), or 4:2:0 (half color resolution both ways). 4:2:0 gives the smallest file size but may reduce color detail.
To reduce file size further, untick Save Exif data and Save thumbnail. These remove metadata and the embedded preview thumbnail.
GIMP Export Quality Preview
The Show preview in image window feature is the most direct way to see the effect of your settings. As you move the Quality slider, the image on screen updates to show the compressed version. The file size display changes instantly. Find the lowest quality that still looks acceptable.
A quality setting in the higher range retains good detail while cutting file size significantly. Need a very small file for web use? Try a lower quality and check the preview.
GIMP Advanced Options for Smaller Files
Subsampling Choices
Subsampling reduces the color information in the image. The default is often 4:2:2 or 4:4:4. For maximum compression, choose 4:2:0. This works well for photographs but may cause color artifacts on sharp edges or text.
Remove Metadata and Thumbnail
In the advanced options, uncheck Save Exif data and Save thumbnail. EXIF data includes camera settings and date stamps. The thumbnail is a small embedded copy of the image used by some file managers. Removing both can save several kilobytes.
Optimize and Progressive
Enable Optimize for a smaller file. Avoid Progressive unless you need the image to load gradually; it adds a small overhead.
Which Settings to Use for Different Needs
For web use where file size matters, start with these settings:
- Set quality to a moderate level in Photoshop (Save for Web) or a similar level in GIMP.
- Enable Optimized (Photoshop) or Optimize (GIMP).
- Set Metadata to None (Photoshop) or uncheck Save Exif data and Save thumbnail (GIMP).
- In GIMP, choose subsampling 4:2:0 for photos, 4:4:4 for graphics with text.
- Check the file size preview and adjust quality up or down by a few points as needed.
For archival or print use, keep quality at a high level, keep metadata, and use 4:4:4 subsampling in GIMP.
Comparing Photoshop and GIMP Workflows
Both editors let you control JPEG compression manually. They differ in how they present the controls. Photoshop's Save for Web gives you a live file size readout and a simple 0-100 quality scale. GIMP's Export As dialog also shows file size and offers subsampling choices that Photoshop's Save for Web does not.
If you need to remove metadata, both programs can do it. Photoshop uses the Metadata menu; GIMP uses checkboxes for Exif data and thumbnail. For progressive JPEGs, both have a checkbox. It is rarely needed today.
For quick batch work, Photoshop's Save a Copy as JPEG is simpler but less precise. GIMP's single Export As dialog gives you all controls in one place.
If you need to reduce file size further after export, you can use an online tool like compressjpeg.onl. The manual controls in these editors give you the most control.