Captions should give enough context for a visitor using a screen reader to understand what the image shows, without being unnecessarily long. They need to provide a clear, factual summary of the main subject, so that someone who cannot see the image still gains the same insight.
A good caption is concise, descriptive, and relevant to the surrounding content.
- Edit an 'Image Gallery' module.
- Enter a caption into the 'Caption' field.
- Select 'Save'.
Keep it brief but meaningful
Aim for one or two sentences (captions can contain up to 1,000 characters) that describe the key subject of the image and its relevance. You don't need to describe every detail - focus on what matters most in the context of your document.
Describe what you see, not what you feel
Stick to factual descriptions rather than subjective language. For example, A team of colleagues gathered around a table in a meeting room is more useful to a screen reader user than A vibrant and energetic team collaboration session.
Avoid redundant phrases
Don't start with "Image of" or "Photo of" - screen readers already identify the element as an image.
Include text that appears in the image
If the image contains a quote, label, or other text, include it in the caption so it isn't missed by visitors who can't see it.
Don't leave captions blank
Even if the caption is set to hidden in your document, it will still be read aloud by a screen reader. A blank or placeholder caption, such as image1.jpg, provides no value and can be confusing.