The 1-3-5 rule: one big task, three medium, five small

The 1-3-5 rule says a day holds one big task, three medium ones and five small ones. Most to-do lists treat every task the same: "Write the proposal" and "Buy stamps" each get one line, as if they took the same time. The 1-3-5 rule gives the day a shape instead of just a length.

Where it comes from

The rule comes from Alexandra Cavoulacos, a co-founder of the career site The Muse, who shared it in a Muse article and later in the book The New Rules of Work, written with Kathryn Minshew. It spread because it fits on a sticky note and its name is the whole explanation. People bend it to their own days, and Cavoulacos expected them to: busy days get fewer slots.

How it works

1. Pick one big thing: a task that takes a good part of your day, like a first draft, a tricky repair or a long application.
2. Pick three medium things, about an hour each: preparing for a meeting, a call with some back and forth, a round of edits.
3. Pick five small things, ten or fifteen minutes each: a quick reply, a payment, a booking.
4. Write the nine down the evening before, or first thing in the morning.
5. When a slot is full, it's full. A new medium task means one of the three medium ones moves to another day.

Why it works

• It makes you think about size. Sorting tasks into big, medium and small is a quick, honest guess at how long they'll take. Most overplanning comes from skipping that guess.
• With only one big slot, you can't fill a day with three huge goals and finish none.
• The quick stuff gets five slots of its own, so it gets done without crowding out the work that matters.
• On a light day you might do 1-3-5. On a busy one, 1-2-3. The shape stays the same.

Where it falls short

• Nine tasks is more than many people finish, once meetings, chores and children are in the mix. A list you never complete teaches you to ignore it. Start smaller.
• A "small" task can open up into an hour. If that happens often, adjust your sizes.
• The rule says what fits, not what to do first. Cavoulacos suggests getting the big one done before lunch; that's a good default.

Fitting nine tasks into Plan's six

Noodle's Plan is built around the Ivy Lee method, so it has a soft limit of six tasks a day. Soft means Noodle never blocks you. When you type a seventh task, it asks "That's more than six for one day. Put it on another day?", and you can tap Another day or keep going. A day with nine tasks shows "9 of 6" in a warning color and asks "Move one to another day?" under the list.

A full 1-3-5 day works, but Noodle will keep suggesting you trim it. Two ways to make the rule fit:

• Batch the small ones. Five small tasks are often the same kind of thing. Group them into one task, like "Admin: pay the water bill, book the car inspection, reply to Ana". That makes 1-3-1, five lines in all.
• Try 1-3-2: one big, three medium and two small, exactly six. Small tasks tend to get done anyway, list or no list.

Make it a habit

• If you only decide one thing, decide the big one. That's close to the daily highlight.
• Be strict with "medium". Anything over an hour and a half is probably big.
• A big task showing "Carried 2 days" is too big for one day. Split it.
• On Friday, scroll back through Plan's past days and count what you finished. Maybe your rule is 1-2-3.

To see 1-3-5 next to the other methods, read daily planning methods, compared; the Plan guide explains every button.