Add text to a photo

How Add Text to Photo works

The image is decoded into a canvas element, redrawn, and handed back as a new file. A canvas lives in the tab; closing it discards the pixels, which is why nothing needs deleting afterwards. Nothing is re-encoded on a server, so no copy of the original survives anywhere you cannot see.

That is the whole architecture: static files, one script, no upload endpoint to leak or log. Close the tab and the work is gone.

Why the outline exists

White text on a bright sky is invisible; black text on a dark shirt is worse. A two-pixel stroke in the opposite tone gives every letter an edge, which is why captions on video thumbnails and memes all use it.

The stroke is drawn first and the fill second, so the glyph stays clean and the outline sits outside it. The shadow is separate and optional: it lifts the text off a busy background without the hard edge a stroke creates.

Full resolution, not preview resolution

The canvas is created at the photo's real pixel size and then scaled down by CSS for the preview. Dragging a caption therefore maps to real pixels, and a 24-megapixel photo exports a 24-megapixel caption rather than a 1200-pixel one blown up.

Font size is stored as a percentage of the image width, which is why the same setting looks right on a phone screenshot and on a DSLR frame.

Where it stops being a good idea

Text over someone else's photo is a copyright question, and text that imitates a screenshot is a trust question. The tool does the drawing; what the caption claims is the part you own.

For legal documents, a caption is not a signature — the sign PDF tool exists for that, and it places an image, not a font.

Good to know

• Works offline once loaded, including on flights and in locked-down networks.
• No file size limit beyond your device's own memory.
• Free to use, with no account and no usage counter.
• Results are produced locally, so they are not logged or shared with anyone.

Questions