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Image Caption Generator

Image & Video Tools

Turn any image into a ready-to-post caption in seconds. Free, browser-based, and no signup — perfect for social posts and feeds.

Updated Jun 15, 2026 Maintained by BoldlyType editors

Image Caption Generator

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What an image caption actually does

Two very different things share the word caption: the visible line printed under a photo, and the alt text screen readers announce to people who can't see the image. A good caption adds context the picture can't carry on its own, a name, a place, a punchline, while alt text describes what's literally shown. The mistake most people make is writing one and skipping the other, or stuffing keywords into alt text. They serve separate audiences, so the same sentence rarely works for both, and search engines read both differently.

Image caption tips

  • Write alt text as a plain description of what's in the frame, not a caption or a keyword dump.
  • Captions can carry tone and context; alt text should stay literal so screen readers convey the image accurately.
  • Keep alt text under roughly 125 characters, since some screen readers cut off longer descriptions mid-sentence.
  • Decorative images need empty alt text, not a description, otherwise screen readers announce clutter that adds nothing.

Image Caption Generator — common questions

Latest questions readers ask us about this topic.

What's the difference between a caption and alt text?

A caption is visible text shown near the image for everyone; alt text is hidden description read aloud by screen readers and shown when an image fails to load. Captions add context, alt text describes the actual content.

How long should image alt text be?

Aim for under about 125 characters. Several screen readers, including older VoiceOver versions, truncate longer alt text, so front-load the important detail and skip phrases like "image of" since the reader already announces it's an image.

Does alt text help with SEO?

Yes, modestly. Search engines use alt text to understand image content for image search and overall page relevance. Write it naturally for accessibility first; keyword-stuffed alt text reads poorly for screen reader users and offers little ranking benefit.

The sub-questions readers ask next — answered, with where to go.

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