Why Does Time Speed Up as You Get Older? What the Research Says

Time seems to speed up with age mainly because adult life has less novelty, so our brains store fewer distinct memories — and when we look back, a period with few memories feels short. Each year is also a smaller fraction of a longer life. Research suggests the effect is strongest when people judge long spans, like a decade, rather than a single day.

The four leading explanations

1. The proportional theory

The oldest explanation is usually credited to the French philosopher Paul Janet in 1877: we judge a span of time against the length of life we’ve lived so far. A year is a fifth of a 5-year-old’s life but a fiftieth of a 50-year-old’s. As the denominator grows, each new year feels smaller. It’s intuitive, but it’s more a description than a mechanism — it doesn’t explain why a boring afternoon can still drag at any age.

2. Novelty and the “holiday paradox”

Psychologist and broadcaster Claudia Hammond, in her book Time Warped, describes the holiday paradox: a week-long trip seems to fly by while you’re on it, yet feels long when you look back. That’s because new experiences create lots of distinct memories. Routine weeks blur together and leave little behind. Childhood is packed with firsts; adulthood, for many people, is full of repeats.

3. Memory-based judgement of duration

Psychologists distinguish between prospective time (how fast time feels while it passes) and retrospective time (how long a period seems looking back). Retrospective estimates lean heavily on how many memories we can retrieve from a period. Fewer stored memories make a year feel shorter in hindsight — which is exactly the “where did the year go?” feeling.

4. Slower “mental images” with age

A newer, physics-based proposal comes from Duke University engineer Adrian Bejan. In a 2019 paper in European Review, he argued that the rate at which the brain perceives changes in mental images declines with age — due to factors like saccade frequency (rapid eye movements) and the growing length and degradation of neural pathways. Fewer images per day would make the day seem to pass faster. It’s an interesting hypothesis, though it’s less established than the memory-based explanations.

What the research actually found

The most-cited study is by Marc Wittmann and Sandra Lehnhoff of Ludwig Maximilian University of Munich, published in 2005 in Psychological Reports. They surveyed 499 people aged 14 to 94 about how fast time felt across different spans, from “very slowly” to “very fast”.

• For short spans — a week, a month, even a year — age made surprisingly little difference. Most people said time felt fast.
• For longer spans like a decade, a pattern appeared: older people tended to feel the time had passed faster.
• Looking back over their lives, participants over 40 said time moved slowly in childhood, then sped up steadily through their teens into early adulthood.

A follow-up study by William Friedman and Steve Janssen (2010) found similarly small age differences — except, again, for how fast the last 10 years felt — and concluded that the feeling of time pressure explained the results better than age itself.

In other words, “time speeds up with age” is mostly a retrospective effect — it’s about how life feels looking back, and it’s tied closely to how busy and routine life has become.

499

participants aged 14–94 (Wittmann & Lehnhoff, 2005)

1877

year Paul Janet proposed the proportional theory

10 yrs

span where the age effect was clearest

How to make time feel slower

You can’t change the clock, but the research points to levers you can pull:

1. 1

   Add small firsts

   New routes, new foods, new places, new skills. Novelty creates distinct memories — the raw material of a year that feels long in hindsight.

2. 2

   Reduce time pressure

   Feeling rushed was linked to time flying faster. Protecting even one unhurried block a week can change how the week feels.

3. 3

   Mark your days

   A one-line journal entry turns a blurry day into a retrievable memory. Over a year, that’s 365 anchors.

4. 4

   Make time visible

   Seeing your weeks as a life calendar or the year as a progress bar keeps time from slipping by unnoticed — you notice weeks as they pass instead of discovering they’re gone.

The goal isn’t more years in your life. It’s more life you can remember in your years.

This is an old insight with new evidence. Two thousand years ago, Seneca argued that life feels short because we don’t pay attention to it — read our summary of On the Shortness of Life for how he put it.