By the NumbersBy the Numbers: What a 30% Hot-Day Water-Demand Surge Looks LikeTranslate the Environment Agency's 30% peak water-demand increase into household litres, cubic metres, and an illustrative metered charge.Calcul8 blog
Practical guides for the numbers behind everyday decisions
Plain-English articles on money, homes, cars, small business, and useful maths. Each post explains the idea, shows where people trip up, and links to a calculator when you are ready to try your own numbers.
Featured · By the Numbers
By the Numbers: Rebuild the July 2026 Energy Cap From Unit Rates
Ofgem's July rates become a worked electricity-and-gas bill, showing why the price cap limits rates rather than a household's total.Latest articles
Browse calculators
By the NumbersBy the Numbers: What a 30% Hot-Day Water-Demand Surge Looks LikeTranslate the Environment Agency's 30% peak water-demand increase into household litres, cubic metres, and an illustrative metered charge.
By the NumbersBy the Numbers: The Cost of Running a Fan for a 12-Day HeatwaveA 50-watt fan, 12 hours a day, 12 hot days and Ofgem's current unit rate become one transparent appliance-cost example.
By the NumbersBy the Numbers: Petrol at 152.29p — Run Your Summer Trip CostTurn the latest official UK petrol and diesel prices into 100, 300, and 600-mile fuel-cost scenarios.
By the NumbersBy the Numbers: How a Seven-Day Average Explains Heat-Related CallsUse seven UKHSA daily NHS 111 call counts to calculate a transparent average and show how a moving window changes.
By the NumbersBy the Numbers: England Had 3% of Average July RainfallExplain why 3% of average rainfall means a 97% shortfall, using clear illustrative millimetre examples.
By the NumbersBy the Numbers: UK Rent Reached £1,388 a MonthTranslate the latest 3.3% UK rent growth rate into monthly and annual pound examples without mistaking an average for a tenancy forecast.
By the NumbersBy the Numbers: What 2.6% UK Inflation Means in PoundsPut June's 2.6% CPI rate against familiar household baselines, then compare food, transport, hospitality, and clothing rates.
By the NumbersBy the Numbers: UK Inflation (April 2026) — What 2.8% CPI Can Mean in PoundsONS reports CPI up 2.8% in the year to April 2026. We translate the percentage into pounds for simple household budget examples.
By the NumbersBy the Numbers: Ofgem Price Cap £1,641/year — Rebuild the Bill From Unit Rates and Standing ChargesOfgem’s April–June 2026 cap headline is £1,641/year for a typical household. We show how unit rates, standing charges, and kWh usage combine to form a bill.Browse by topic
By the Numbers
- By the Numbers: Rebuild the July 2026 Energy Cap From Unit Rates
- By the Numbers: What a 30% Hot-Day Water-Demand Surge Looks Like
- By the Numbers: The Cost of Running a Fan for a 12-Day Heatwave
- By the Numbers: Petrol at 152.29p — Run Your Summer Trip Cost
- By the Numbers: How a Seven-Day Average Explains Heat-Related Calls