Why does time seem to go faster as we get older?

Time seems to go faster as we get older mostly because of how memory works. When life is full of new experiences, the brain stores lots of detailed memories, and looking back, that period feels long. As routines settle in, fewer new memories are made, so weeks and years look shorter when we remember them. A few other ideas add to this, but novelty is the big one.

Idea one: a year is a smaller slice of your life

For a five year old, one year is a fifth of everything they have lived. For a fifty year old, it is a fiftieth. This proportional idea goes back to the 19th century French philosopher Paul Janet. It is simple and easy to remember, though it does not explain everything.

Idea two: fewer new memories

Childhood and early adult life are packed with firsts: first school, first job, first trip abroad, first home. Each one leaves a strong memory. In later years many days look alike, and the brain does not keep separate memories of each one. When we look back, a year with few distinct memories feels like it passed quickly.

The psychology writer and broadcaster Claudia Hammond calls a related effect the holiday paradox. A week away somewhere new seems to fly by while you are there, but feels long when you remember it, because it was full of new things.

Idea three: how we notice the present

When we are busy or absorbed, we stop checking the clock and time feels quick in the moment. When we are bored or waiting, every minute drags. Many adults say the days are long but the years are short, which fits both effects working together.

Can you slow it down?

You cannot add hours to a year, but you can make a year feel fuller when you look back on it. A few things that help:

• Do something new on purpose, even small: a different route, a new recipe, a place you have never been.
• Break up routines with markers, like a short trip each season or a new skill each year.
• Pay attention: put the phone away and notice where you are, so the day leaves a memory.
• Write one line in a diary each evening. Even a few words make days easier to tell apart later.

Autumn is a good time to try it. The days get shorter, but the year does not have to feel that way.