28 everyday tools, grouped by the question behind them
These are the calculations that fall between subjects — what an appliance really costs to run, whether a subscription earns its place, how much a wasted hour is worth. Individually small, they add up to most of the decisions a household makes in a month.
Every calculator in this section now carries a full explanation: what it works out, the method, a worked example, the mistakes people make, and — where it matters — what the tool cannot tell you. Pages covering draws and lotteries include support information, and pages that rest on figures you must obtain elsewhere say so plainly.
Start here
If you are not sure where to begin, these tools answer the questions readers ask most often in this section.
Household running costs 5 tools
What appliances, standby power, water and connectivity actually cost across a year.
The value of your time and money 5 tools
Putting a defensible number on an hour, and testing whether a recurring cost earns it.
Occasions, gifts and giving 4 tools
Budgets for the events that arrive every year and are planned for every year at the last minute.
Waste, recycling and footprint 3 tools
Bin capacity, recycling volume and a broad estimate of household emissions.
Odds, draws and waiting 5 tools
Honest probabilities for competitions, raffles and waiting lists, including the ones you will not like.
Home admin and organisation 4 tools
Inventory, fair division of work, noise and structured decision-making.
Printing and labelling 2 tools
Getting printed codes physically large enough to scan reliably.
Common questions
Where do I find an appliance's power consumption?
Usually on a rating plate on the back or underside, or inside the door on white goods, given in watts or as a voltage and current you can multiply together. Energy labels give an annual figure for fridges, freezers, washing machines and dishwashers, which is more reliable than a nameplate wattage because it reflects a realistic duty cycle. A plug-in energy monitor is the most accurate option and costs very little.
Which electricity price should I enter?
The unit rate from a recent bill, in pence per kilowatt-hour, rather than a headline national figure. Remember that the standing charge is a fixed daily cost that does not change with usage, so it should not be included when comparing one appliance against another.
Is standby power really worth worrying about?
Individually, no — a device drawing two watts costs a few pounds a year. Collectively it is less trivial: a typical home has a surprising number of always-on devices, and the total often lands somewhere between £30 and £80 a year. The checker exists to show you which ones dominate, because it is usually two or three items rather than everything.
How should I use the time value calculator?
As a comparison tool rather than a wage. It gives you a figure for what an hour is worth to you, which makes questions like whether to pay for delivery, drive further for cheaper fuel or outsource a job into arithmetic rather than instinct. It works best when you use the same figure consistently across decisions.
Are the odds calculators accurate?
The probability maths is exact for the assumptions stated: a fair draw, a known entry count and independent entries. Real competitions frequently break those assumptions — multiple entries per person, unpublished entry numbers, regional weighting or skill-based judging. Where the entry count is unknown, the result is only as good as your estimate of it.
Is anything I enter stored?
No. Costs, inventories, subscription lists and personal details are processed entirely within your browser and are never transmitted or kept as calculator records.
Related subjects
Questions rarely sit inside a single subject. These sections cover the calculations most often needed alongside everyday decisions.