PDFConvertersOnline.comHow to compress a JPEG
- Add your .jpg or .jpeg photos. A whole folder from your camera or phone is fine.
- Leave quality at 75% for everyday use, or switch to Target size and enter a KB limit.
- Compress, check the slider view, and download the lighter copies.
How JPEG quality actually works
JPEG splits a photo into small 8×8 pixel blocks and describes each block with a set of wave patterns. The quality number decides how precisely those patterns are stored. High values keep subtle texture; low values round it off, which saves bytes but eventually shows up as blocky patches and halos around sharp edges. The relationship is not linear: going from 100% to 85% often halves the file with no visible change, while going from 40% to 20% saves much less and looks much worse.
| Quality | Typical use |
|---|---|
| 85–95% | Prints, portfolios, photos you may edit again |
| 70–80% | Websites, blogs, online shops, email |
| 50–65% | Thumbnails, previews, forms with strict size caps |
| Below 50% | Only when a limit leaves no choice; artifacts become visible |
Why camera JPGs are so big
Phones and cameras save at very high quality and add a block of metadata: lens, exposure, date, often GPS coordinates and a small embedded preview. A 12-megapixel shot straight from a phone can be several megabytes. Re-saving at a sensible quality removes the extra weight and the metadata together, so a picture you share no longer reveals where it was taken.
Avoid repeated re-saving
Every time a JPG is opened and saved again, a little more detail is rounded off. Compress from the best copy you have, ideally the original from the camera, rather than from a file that has already been through a messaging app or social network. If you need several sizes, make each one from the original instead of compressing a compressed file.
JPG, or something else?
JPG is still the safest format for photos: every browser, phone, printer and upload form accepts it. For graphics with flat colors, sharp text or transparent areas, PNG is a better fit, and Compress PNG handles those. If you control the website where the image will appear, JPG to WebP or JPG to AVIF can shave off more bytes at the same look.
Checking the result
Artifacts show up first in three places: smooth skies and walls, where faint blocks appear; the edges of dark text on a light background, where a gray fringe appears; and skin, which can look waxy. Drag the before/after slider across those areas. If they look fine, you can often go a few points lower; if not, raise the slider and compress again from the original file, not from the compressed copy.
More ways to use this tool
Frequently asked questions
What quality should I pick for a website?
Around 75% is a good start. Check the result at full size on the slider; if you see smudgy skin or blocky skies, go up to 80–85%.
Is JPEG the same as JPG?
Yes. They are two spellings of the same format. Both .jpg and .jpeg files are accepted and the output keeps the .jpg extension.
Will the photo lose its date and location?
Yes, the re-saved copy has no EXIF data, which includes the capture date and GPS position. Keep your original if you rely on that information for sorting albums.
Why did one file stay the same size?
It was already compressed as much as the chosen quality allows, so the tool kept the original rather than give you a bigger copy.
Can I shrink a JPEG to a specific size, like 100 KB?
Yes. Switch to Target size and type the number, or open a ready-made page such as Compress Image to 100KB.
Can I compress JPGs on my phone?
Yes. Open this page in your phone's browser, choose photos from your gallery and download the smaller copies. Large batches take longer on a phone, so work in small groups.