1Upload the JFIF images you want to mark, already at their final size — watermarking comes after resizing, not before it.
2Upload a transparent PNG logo or type your text, then choose the font, the colour and the opacity.
3Set the position, or switch to a tiled repeat when a single corner mark would be too easy to crop away.
4Download the watermarked JFIF file; nothing else is added to it.
Watermark JFIF FAQ
How does Watermark JFIF place the mark?
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Concretely, the mark is composited onto the decoded image and the result is re-encoded once, so add the watermark last, after any resizing or compression, rather than watermarking a master you will process again. You control the position, the size and the opacity, and the same settings are applied consistently across everything you upload.
Can I use my own logo, or only text?
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Either. Upload a transparent PNG logo, or type text and choose the font, colour and opacity. A tiled repeat is available when one corner mark is too easy to crop away.
Does the file format affect how the watermark comes out?
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It does. JFIF is a plain JPEG bitstream under the original 1992 interchange header, which is why some viewers show it as a generic image and cameras still emit it. That governs how cleanly a semi-transparent mark can be blended into the underlying content.
Anything specific to JFIF worth knowing?
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Yes — many editors silently rewrite a JFIF as an ordinary JPEG on save, so keep the original if the .jfif extension itself matters to whatever consumes the file. It affects when in your workflow the mark should be applied.
Does a watermark actually protect my work?
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It deters casual reuse and it credits you; it is not security. A corner mark can be cropped and a faint one can be painted out. If protection matters, a large semi-transparent mark across the subject is far harder to remove than a discreet one in a corner.
Should I watermark before or after resizing?
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After. Watermark the final deliverable at its final size, so the mark stays legible and proportionate. Watermarking a master you will process again means the mark gets resampled and compressed along with everything else.
What can I upload to Watermark JFIF?
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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 Watermark JFIF?
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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 Watermark JFIF lower the quality of my JFIF images?
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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 Watermark JFIF on several JFIF images at once?
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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.
What happens to EXIF and colour profile data?
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Camera EXIF (ISO, shutter, lens, GPS) and the embedded ICC profile are carried across by default, because dropping the profile is what makes colours shift on re-import. Use the privacy option to strip metadata before download if you are about to publish the file.
Does Watermark JFIF cost anything?
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No. Watermark JFIF is free with no account, no watermark on the output and no signup wall in front of the download. Uploads are deleted automatically a short time after the job finishes.
