When JPG to TIFF turns JPG into TIFF
A print workflow asked for TIFF and you only have a JPG.
What JPG to TIFF changes in the picture
The browser writes a TIFF from the JPG pixels. The TIFF is not sharper than the JPG, and it is larger.
If the shop needs CMYK or a specific DPI, set that in their software. This page only changes the container of the picture you already have.
When JPG to TIFF is the right page
JPG to TIFF sits on this site because JPG and TIFF are not interchangeable, even when they look similar in a file list. A print workflow asked for TIFF and you only have a JPG. Portals, printers, and chat apps that reject HEIC, WEBP, or AVIF are asking for JPG. Print shops and archives ask for TIFF. Everyone else usually wants JPG.
The browser writes a TIFF from the JPG pixels. The TIFF is not sharper than the JPG, and it is larger.
What you give up by leaving JPG
JPG is the photo file almost every form, email app, and Windows program accepts. JPG is lossy. Saving it again softens fine detail. It cannot store transparency.
Keep the camera original, whether that was HEIC, PNG, or a RAW file you exported earlier.
What you gain, and do not gain, with TIFF
The download has to be TIFF, because that is the format the next step named. Print shops and archives ask for TIFF. Everyone else usually wants JPG. A high-quality scan can live in TIFF without JPEG damage, if it started that way.
Multi-page TIFF is not rebuilt as a text document here. You get the picture the browser could read.
A test that matches the real file
Start from the question the other software asked. If it asked for TIFF, JPG to TIFF is the matching page. If it asked for something else, switch tools instead of hoping a similar extension will pass. A print workflow asked for TIFF and you only have a JPG. The browser writes a TIFF from the JPG pixels. The TIFF is not sharper than the JPG, and it is larger. The limit is the part people skip, and it is the part that decides whether the download is usable. If the shop needs CMYK or a specific DPI, set that in their software. This page only changes the container of the picture you already have. The file stays in your browser and is not uploaded. The limit is 100 MB. Keep the original until the download has been opened in the program that will use it. Check three things in the download: it opens, the JPG material you cared about is still there, and the file size or the layout is what the form described. A new extension alone is not those three things. If a portal, a teacher, or a client rejects the file, send them the original JPG as well when you are allowed to. JPG to TIFF is a convenience copy. It is not a new master. Photos fail uploads for three separate reasons: the format name, the pixel size, and the kilobyte size. JPG to TIFF only does the JPG to TIFF step. If the form also prints a pixel size or a 20 KB or 50 KB cap, do that step with the matching tool, starting from the original each time. A second lossy save will not recover detail.
Here is the decision for JPG to TIFF. You start with JPG and you stop when a real program accepts TIFF. It is small and universal for photographs. A TIFF made from a JPG cannot be sharper than that JPG, and it is larger. If those two sentences describe a tradeoff you do not want, do not convert. Renaming the extension by hand will not do this job. Running the tool twice on its own output will not do it either.
If the shop needs CMYK or a specific DPI, set that in their software. This page only changes the container of the picture you already have.
A related step, if you still need one, is TIFF to JPG.
Other jobs start from the homepage, where each tool is named for the conversion it actually does.