Alt text is a short written description of an image that screen readers read aloud for blind and low-vision people, and that shows in place of the image when it can't load.
Snapshot writes the alt text for a photo, with its caption and hashtags.
Also used in: Photo Collage Maker
Without alt text, a photo is silent to anyone using a screen reader: they hear "image" and nothing else. Instagram, Facebook, X, LinkedIn, Pinterest, Bluesky and Mastodon all have a field for it, usually under advanced or accessibility settings when you post, and some fill in an automatic description if you don't.
A good one says what matters in the picture in a sentence or two; it isn't the caption again, and it doesn't need hashtags.
A wedding photographer posts a first-dance photo.
The caption tells the story of the song; the alt text reads "A couple slow-dancing in a barn lit with string lights, guests watching from the edges." A follower using a screen reader now knows what the photo shows, which the caption alone never said.
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