Is the human attention span really eight seconds?

No. That figure came from a corporate report, was attributed to a body that says it never produced it, and has no research behind it. It has been repeated widely enough to feel established, which is how most durable myths work.

Has attention span actually got shorter?

There is no good evidence for a population-level decline, partly because there is no single measure to compare across decades. What is well supported is that switching has become far cheaper and more available.

Attention Span: The Goldfish Claim Is Not True

Attention span: How long attention can be sustained on one thing — a figure that varies enormously with the task, the person, and how interesting the thing is.

Where the idea comes from

The concept is ordinary; the famous number is not. The "human attention span has fallen to eight seconds, below a goldfish" claim circulated from a 2015 corporate report, was attributed to a source that had not produced it, and does not appear in any research literature. Attention researchers have repeatedly pointed out there is no single measurable human attention span to have fallen.

How it shows up

Reading a page and arriving at the bottom having absorbed nothing
Being unable to sit through something you chose and are enjoying
Reaching for a second screen during the first one

What actually helps

Match the block to the task rather than to an idealised number
Remove the option to switch, since attention mostly ends by switching rather than by running out
Notice what you can attend to for hours — that number is your capacity, and it is task-dependent

Where the popular version overreaches

Attention span is not a single quantity you have, and it has not been measured falling generation over generation. What has changed is the number of available alternatives at any moment, which is a different claim and a much better supported one.

Common questions

Is the human attention span really eight seconds?: No. That figure came from a corporate report, was attributed to a body that says it never produced it, and has no research behind it. It has been repeated widely enough to feel established, which is how most durable myths work.
Has attention span actually got shorter?: There is no good evidence for a population-level decline, partly because there is no single measure to compare across decades. What is well supported is that switching has become far cheaper and more available.

Sources

BBC — Busting the attention span myth

Context switching
Context switching is moving between tasks that require different mental setups. The cost is not the seconds spent moving — it is rebuilding what you were holding in your head.
Attention residue
Attention residue is the part of your attention that stays behind on the last task after you have moved to the next one. It is why a two-minute interruption costs far more than two minutes.
Deep work
Deep work is sustained, undistracted concentration on something cognitively demanding. The idea is simple; the part people skip is that it has to be scheduled against the rest of the day.
A plain glossary of focus
The vocabulary of attention and procrastination, with sources and honest caveats.
Executive dysfunction
Executive dysfunction is difficulty with the mental processes that turn intention into action — planning, starting, switching, and holding a goal in mind. Here is what it looks like day to day, and what actually helps.
Task initiation
Task initiation is the executive function that gets you from deciding to doing. For a lot of people it is the only part that is broken — and it responds to different tools than focus does.