2Pick your effects — grayscale, sepia, invert, blur, sharpen, brightness, contrast and saturation — and set the strength of each.
3Apply them all in a single pass rather than running the tool repeatedly, which is what accumulates visible damage.
4Download the filtered JPG file, and keep your original: it is the only undo you have.
JPG Filters FAQ
Can I apply the same look to a whole set?
+
Yes. One filter configuration is applied across the batch, which is how you get a visually consistent gallery rather than a set of individually-tweaked images that almost match.
How does JPG Filters apply an effect?
+
Concretely, the filter is a per-pixel transform applied to the decoded image, so the file is necessarily re-encoded once — apply every filter you want in a single pass rather than stacking runs. You pick the effect and its strength and the transform is applied to the whole file at once.
Anything specific to JPG to keep in mind?
+
Yes — every save re-runs the quantiser, so repeatedly editing and resaving a JPG compounds generation loss even if you never lower the quality slider. That is often the difference between an effect looking clean and looking banded.
Can I undo a filter after downloading?
+
No — the effect is baked into the output pixels, which is the point of applying it. Keep the original file; that is your undo. Grayscale and blur in particular discard information that genuinely cannot be recovered.
What can I upload to JPG Filters?
+
Anything in the lossy raster family — JPG, JPEG, JFIF and WebP — plus the lossless formats (PNG, BMP, TIFF) if you want to mix them in one batch. The format is read from the file header, not the extension, so a photo saved with the wrong suffix still goes through.
Is there a file size limit on JPG Filters?
+
Yes: free accounts process images up to 25 MB each, which covers essentially every camera JPG and phone photo; the work is done by libjpeg-turbo and libwebp, the same libraries a desktop editor links against. Larger files are the one thing the free tier will stop you on, and the limit is per file rather than per batch.
Will JPG Filters lower the quality of my JPG images?
+
A lossy source is already the result of one quantisation pass, and any operation that has to re-encode adds a second. Where the job can be done without touching the pixel data we do that instead, and where it cannot you choose the quality factor yourself rather than getting a fixed default.
Can I run JPG Filters on several JPG images at once?
+
Yes. Drop the whole set into the upload area and they queue in parallel with identical settings — that is the main reason to do this in a browser rather than one file at a time in an editor. Free accounts run one file per batch; a pass lifts that.
Why does a EPUB site host JPG Filters?
+
EPUB.to is built around the open eBook format — XHTML in a zip, reflowable by design, and readable on hardware nobody has thought about the layout for. A book is a zip full of markup, images and fonts, so almost every job people bring to an eBook site is really a job on one of those things. JPG Filters runs on the same upload and the same account as the conversions because that is where it is needed.
What should I do with the result once JPG Filters is finished?
+
The converter on this site moves books between EPUB, MOBI, AZW3, PDF and DOCX, so a title ends up on whatever hardware is actually going to read it. Doing that after JPG Filters means the conversion is made from the version you settled on, not from the one you were still fixing.
Is JPG Filters here the same tool the sibling sites run?
+
The engines are shared — the same toolchain, the same workers, the same limits. What a EPUB site adds is a view on reflow: which of these operations a reflowable book genuinely supports, and which ones only make sense on the fixed-layout media inside it. It also starts from one fact about the format this site is named after: the book is a zip of XHTML with a manifest, so the text costs almost nothing and every decision that matters is about the embedded images and font subsets.
Do I need an account, and does anything get kept?
+
No account, and nothing is kept: uploads are deleted from the workers shortly after the job finishes, nothing is read and nothing is indexed. Free accounts exist for history and batch size, not for access.
