File-format guide
Should you save as JPG, PNG or WebP?
The best choice depends on what the image contains and where it will be used. No single format is best for every photograph, graphic and publishing platform.
Last reviewed: 31 August 2026
| Format | Usually best for | Main limitation |
|---|---|---|
| JPG | Photographs and images with many colours or gradual tones | Lossy compression can soften text and sharp edges; no transparency |
| PNG | Screenshots, diagrams, logos, flat graphics, text and transparency | Photographic files can be considerably larger |
| WebP | Smaller web images, with lossy or lossless compression and optional transparency | Not every social platform, publishing form or older application accepts it |
Choose JPG for most photographs
JPG is widely accepted and efficiently compresses photographs. A high-quality JPG is normally the safest choice when publishing an ordinary camera image to a social platform. Lowering quality reduces file size, but excessive compression introduces blocks, ringing and softness around detailed edges.
Choose PNG for sharp graphics and transparency
PNG uses lossless compression. It is useful for screenshots, interface images, illustrations with flat colours, logos and graphics containing small text. It can also preserve transparent areas. The tradeoff is that a photographic PNG may be much larger than an equivalent JPG without providing a visible benefit after the social platform processes it.
Choose WebP when compatibility is known
WebP can produce compact images and supports both transparency and lossy or lossless compression. It is an excellent format for many websites. Social-media and third-party upload systems do not all treat it consistently, so verify that the intended destination accepts WebP before depending on it.
Simple default: use JPG for a photograph, PNG for graphics or text, and WebP for web delivery when compatibility has been confirmed.
Quality percentage is not resolution
Pixel dimensions describe how many pixels the image contains. The export-quality setting controls how strongly a lossy format compresses those pixels. A 1920 × 1080 file can still look poor if it was created from a tiny source or saved repeatedly at low quality. Conversely, maximum quality does not restore detail that is missing from the source.
What happens after social upload?
Many social platforms create their own versions regardless of the format you selected. Preparing the correct dimensions and a clean source reduces unnecessary work for the platform, but the uploaded file may still be converted or compressed. Keep your original separately and treat the PostPrep output as a publishing copy.
Formats available in Gecko PostPrep
PostPrep can open JPEG, PNG and WebP images and save finished versions as JPG, PNG or WebP. PNG is saved losslessly. JPG and WebP include a quality control so you can balance detail and file size.
For a broader technical reference, see the MDN guide to image file types.
Create the format you actually need
Choose the placement, adjust the crop and select the output format locally.
Open Gecko PostPrep →