Add Text to Image
Processed entirely in your browser. Nothing is uploaded.
A share of the image height, so it scales with the picture.
Result
The font size is a percentage of the image height rather than a pixel value, so the same setting reads the same way on a phone photo and a full-resolution export. The outline is stroked behind the fill, which keeps light text legible over a busy or unpredictable background — the usual reason a caption disappears. A visible watermark discourages casual reuse but is not protection: it can be cropped or painted out.