Compress a JPEG with a quality slider and quick presets. Watch the file size drop in real time instead of guessing at a target number.
Last updated: August 2026
1 to 100%
Quality Range
4 Presets
Plus Full Slider
JPEG
Always Output
Private
No Uploads
Drop image here to compress
JPEG, PNG, WebP, AVIF, HEIC accepted. Output is always JPEG.
Need to hit an exact file size instead, like 100KB for a form? Use the compress under 100KB tool instead of guessing at a quality percentage.
Drop or select your image
JPEG, PNG, WebP, AVIF or HEIC. Nothing is uploaded, it stays on your device.
Pick a preset or drag the slider
Highest Quality, Balanced, Smaller File, Smallest File, or an exact percentage.
Watch the size update live
Compressed size, percentage saved and dimensions update as you adjust.
Download your JPEG
Once you're happy with the result, save the file to your device.
Other things people do with JPEG files
There's no single correct quality number, only tradeoffs. Here is roughly what to expect at each range.
90 to 100 percent
Close to lossless. File size savings are small since the encoder is barely trimming anything. Reserve this range for images you plan to edit again later.
75 to 90 percent
The recommended range for most photos. Meaningful file size reduction with no visible difference from the original at normal viewing sizes.
50 to 75 percent
Noticeably smaller files. Fine detail starts to soften under close inspection, but the image still looks clean on a screen or in a feed.
Below 50 percent
Aggressive compression with visible blockiness around edges and flat color areas. Only worth it when file size matters more than appearance.
JPEG compression works by discarding image data that the human eye is least likely to notice, mostly fine color variation rather than brightness detail, and by grouping pixels into small blocks that get encoded more efficiently when they're similar to their neighbors. The quality setting controls how aggressively that discarding happens. A higher number keeps more of the original detail, a lower number throws more away in exchange for a smaller file. That relationship is smooth and continuous, which is exactly what a slider is built for.
A target file size in kilobytes works well when you have an actual number handed to you, like a form that rejects anything over 100KB. But most of the time, people compressing a JPEG don't have a specific number in mind at all, they just want the file smaller without a visible quality hit. Forcing that decision through a KB target means the tool has to guess at a quality percentage on your behalf and search for it, when you could just set the quality directly and see the result immediately. That's the gap this tool fills alongside the target size tools elsewhere on the site.
JPEG is a lossy format, meaning some image data is permanently discarded every time a file is encoded. If you take a JPEG that has already been compressed once and run it through a compressor again, the encoder is working from data that's already missing some of the original detail, and it discards further data on top of that. Repeat the cycle a few times and the cumulative loss becomes visible, an effect commonly called generation loss. The fix is simple: always compress from the original photo, whether that's a camera file, a phone photo, or an uncompressed export, rather than re-running an already-compressed JPEG back through a compressor.
It's a common assumption that setting quality to the maximum produces a perfect, lossless copy of the original. It doesn't, JPEG is a lossy format by design regardless of the quality setting, and even at 100 percent, a small amount of data is discarded during the block-based encoding process. The difference at that range is invisible to the eye but not mathematically zero. If you genuinely need a lossless result, a format like PNG is the right choice instead, and the JPG to PNG converter handles that conversion, though PNG files are typically much larger for photographic content.
Compressing a JPEG that's already been compressed once
Every re-encode of a lossy JPEG throws away a little more detail, an effect known as generation loss. Always start from the original photo rather than a file that has already been through a compressor.
Defaulting to maximum compression
Dragging straight to the smallest file size setting usually isn't necessary. Most photos hold up fine at 75 to 90 percent quality with file size savings that are still substantial.
Assuming a higher percentage always means a better result
Past roughly 90 percent quality, the file size keeps climbing while the visible improvement flattens out. There is a point where higher quality stops paying for itself.
Not checking the pixel dimensions first
A photo with far more resolution than it needs will always be bigger than necessary, regardless of quality setting. Resizing down to the dimensions you'll actually display reduces file size before compression even starts.
Using this tool when a portal states an exact KB limit
A quality slider is great when you're choosing your own tradeoff, but if a form says the file must be under a specific number like 100KB, a target size tool guarantees you hit it instead of guessing at a quality percentage.
80 to 85 percent is the sweet spot for most photos. At that range, the file size drops significantly compared to the original while the compression itself stays invisible to the eye at normal viewing sizes. Quality below 60 starts to show visible artifacts around fine detail and high-contrast edges, so treat that as a last resort rather than a default.
A quality slider matches how JPEG compression actually works, by trading detail for file size along a continuous scale. A target size in kilobytes is useful when a form or portal states an exact limit, which is what our compress to size tools handle. When you don't have a specific number to hit and just want a smaller, clean JPEG, adjusting quality directly gives you more control over the actual tradeoff you're making.
Yes, if you keep recompressing an already-compressed JPEG, quality degrades a little more each time, an effect known as generation loss. Always compress from the original, highest-quality source file rather than a JPEG that has already been through a compressor once, including a previous save from this same tool.
Yes. The tool accepts JPEG, PNG, WebP, AVIF and HEIC as input and always outputs JPEG. This is useful for iPhone photos saved as HEIC or screenshots saved as PNG, since both convert and compress in a single step.
Yes. The image is decoded to raw pixels and re-encoded during compression, so EXIF metadata, including GPS location, camera model and timestamps, does not carry over to the compressed file.
No. All compression happens entirely in your browser using WebAssembly. Your image never leaves your device. You can verify this by disconnecting from the internet after the page loads, the tool still works.
No sign-up. No uploads. Drop your image above and download the compressed version in seconds.
