Add text to a photo

What adding text to a photo is for

Adding text to an image is handy to create a watermark with your name or your channel's, to caption a screenshot, to prepare a cover, or simply to share a line over a background image.

The readability trick

Light text with a dark outline (or the other way around) stays readable on any background, light or dark. It's the trick used in subtitles and video thumbnails: leave the outline on if the photo has mixed colors.

Why white text sometimes cannot be read

White lettering on a photo works as long as there is something dark beneath it, and vanishes the moment it crosses a sky or a pale wall. Since a photo does not have a single colour, the only solution that always works is detaching the text from the background instead of hoping for contrast: an outline in the opposite colour, a soft shadow, or a semi-transparent band behind the letters.

The dark outline around light text is the subtitle technique, and it is not a stylistic flourish: it is the only way to stay legible on an image that changes. The semi-transparent band is more elegant and better suited to long text, because it does not tire the reader.

Where the text should go

Not in the centre, which is where the subject is, and not hard against the edges. The practical rule is leaving a margin of about five per cent of the side: any tighter looks like a layout mistake, and on some platforms the border gets cut by automatic cropping.

On social media there are two zones to avoid entirely: the lower part, where apps put captions, usernames and buttons, and the corners of stories, covered by the interface. Anyone designing an image for a story should keep the text inside the central rectangle, the only portion guaranteed visible on every phone.

Watermarks, and what they can and cannot do

A watermark does not prevent copying: anyone can crop it out or paint over it. It serves two different and more modest purposes, but real ones: making casual reuse awkward, and letting whoever sees the image elsewhere know where it came from. That is why it works better when it is discreet but crosses the subject, rather than sitting in a corner a crop can remove.

What really protects is not the watermark but the proof of having created the image: the high-resolution original, the working files, the capture metadata. A watermark is a sign, not a lock.

The things that ruin lettering

The resizing afterwards: text written on a large photo and then reduced becomes illegible, because thin letters disappear. Better to write at the final size, not before. And compression: the sharp edges of letters are exactly what JPEG handles worst, so an image with text should be saved at higher quality than usual, or as PNG if there is a lot of text.

Finally the typeface: thin, elegant fonts hold up badly over a photograph, while faces with thick strokes stay legible even as thumbnails. An image for social media is looked at small on a phone, not full screen: that is the size it should be checked at.

Nearby tools

To cover a part there is Blur part of a photo, for the right format Resize photo and for size Compress image. For a hand-drawn signature there is Online signature, and to join several images Merge images.