Three numbers, and only one of them is hard
Downsizing has an arithmetic shape that is usually skipped. What you own, in cubic feet. What the new place holds, in cubic feet. The difference, which is what has to leave. The first number can be measured, the second can be estimated from floor area, and the third falls out. What makes it feel like a mood rather than a calculation is that the third number is never worked out, so the process runs as a series of individual decisions with no target and no end.
Converting a floor area into a volume of goods is the step that needs a judgement. The figure used here is cubic feet of belongings per square foot of home, and the default of 0.8 corresponds roughly to a normally furnished house — around 800 cubic feet of goods in a thousand square feet. Set it to 0.6 if you want a place that feels uncluttered with empty cupboards, and to 1.0 if you are content with full storage everywhere and no spare corner. That single number moves the answer more than anything else on the page, and it is a decision about how you want to live rather than a measurement.
Why the allocation is weighted by room
Spreading the gap evenly across the house would be arithmetically tidy and practically useless, because rooms differ enormously in how much of their contents is genuinely optional. A bedroom is mostly things in daily use. A garage, basement or loft is mostly things that went in and never came out, which is a different category of possession entirely: it has already demonstrated, over years, that nobody needs it.
| Room group | Typical optional share | What the decisions feel like |
|---|---|---|
| Garage, basement, loft | 60-70% | Fast. Most of it has not been touched since it went in. |
| Office, study, hobby room | 35-45% | Paper is quick, equipment is slow, the hobby you might restart is slowest |
| Kitchen | 25-35% | Duplicates and single-purpose gadgets go easily; the rest does not |
| Living and dining | 20-30% | Furniture-led. Often about what fits rather than what is wanted. |
| Bedrooms | 15-25% | Clothes dominate and the decisions are slow per cubic foot |
Those shares are the fields at the top of the page and they are your judgement, not measurements. The practical use of the weighting is ordering: it tells you that most of the gap can be closed in the rooms with the fast decisions, and that is where to start. Momentum is a real resource in this task and it is built in the garage, not the wardrobe.
Sell, donate, discard, and the trap in the first one
Selling looks like the obvious route because it recovers money, and it is the one that quietly consumes the schedule. Photographing, listing, answering messages, arranging to meet, waiting for somebody who does not turn up, relisting — per cubic foot it is many times slower than a car journey to a charity, and the amount recovered on ordinary secondhand household goods sold against a deadline is small. The buyer knows the deadline exists, and the price reflects it.
That does not make selling wrong. It makes it worth reserving for a small number of items with real value, decided early enough that they can sit on a listing for weeks rather than days. Everything else moves faster and with less friction through donation or disposal. The split on this page is a field precisely so you can see what a 60 percent sell target does to the hours before you commit to it.
Storage is a decision deferred at a monthly rate
The storage field exists to make one thing visible: renting space does not close the gap, it moves it somewhere with a bill attached. There are good reasons to do it. A genuinely temporary situation with a known end date, a house sale that has not completed, a job posting for a fixed term — in all of those, storage buys time you actually need.
What it does badly is stand in for a decision. Without an end date, the monthly charge continues, the contents become steadily less relevant, and the eventual clear-out happens years later under exactly the same time pressure as this one, with a few thousand pounds of rent already spent. If you are considering it, put a real end date on it and price the whole period rather than the month. There is a calculator on this site for that, and the number it produces is usually larger than people expect.
Questions people ask
How much do I need to get rid of when downsizing?
The difference between your current volume and what the new place holds, which is the top line of this page. To use it you need a real figure for what you own — worked room by room rather than taken from a bedroom count — and a judgement about how full you want the new place to be. Expressed as a share, moving from a house to a place two thirds the size means shedding roughly a third of everything, and the reason that feels understated is that it is measured in cubic feet rather than in decisions. A third of the volume is far more than a third of the choices.
Where should I start decluttering?
The garage, the basement and the loft, in that spirit if not that order. They hold the largest volume in most homes, they have the highest share of things that are genuinely optional, and the decisions are fast because the contents have already proved over several years that nobody needs them. Starting in a bedroom or a kitchen is starting with the slowest decisions per cubic foot, which is how people spend three weekends and shift almost nothing. Volume first, sentiment last.
Is it worth selling things before a move?
For a small number of items with real value, yes, and it needs to start early enough that a listing can sit for weeks. For ordinary household goods sold against a moving date, the arithmetic is poor: the time per item is high, the price achieved is low, and the deadline is visible to every buyer. Put your own realistic figure into the resale field and look at what the sell column costs in hours. Most people who do that move a large part of the sell share into donation, which is one car journey for a load rather than an evening per item.
Should I put things into storage instead of getting rid of them?
Only with an end date you can name. Storage is genuinely useful when the constraint is temporary — a sale that has not completed, a posting that ends, a renovation. It is a poor substitute for deciding, because the monthly charge continues indefinitely, the contents become less relevant every month, and the clear-out still has to happen eventually under the same pressure. The storage field above deliberately does not reduce the gap for that reason: it shows the volume as rented rather than resolved.
How long does downsizing take?
Longer than the packing, which is the part people schedule. The model here uses minutes of deciding per cubic foot, and even a modest figure produces a total in the tens of hours for a normal house, spread across evenings and weekends alongside everything else a move demands. The figure also understates the end of the process, because the last third of any declutter is the difficult third and takes far more time per cubic foot than the garage did. If the weekly hours the calculator produces look impossible against the weeks remaining, that is the useful output — it means starting now or moving more than you meant to.