Ultimate UK Tyre Size Comparison Guide
Compare UK car tyre sizes, calculate speedometer error, check sidewall markings (205/55 R16), and learn MOT axle rules with our ultimate comparison guide.
The Pro Calculator UK blog
Plain-English guides on UK money, tax and home-improvement maths — no jargon, just the numbers explained.
Motoring
Fitness
Ultimate Running Pace to Finish Time Chart
Master your running target splits for 5K, 10K, half marathon, and marathon. Includes min/km to min/mile charts, negative split tactics & treadmill speed guide.
Personal Finance
Smart Wedding vs House Deposit UK Guide
Compare average UK wedding costs (£20,000+) vs first-time buyer house deposits. Learn compound growth losses, Lifetime ISA bonuses, and budget split strategies.
Personal Finance
Slash Lunch Costs: UK Meal Prep Savings Guide
Discover how much money meal prepping saves in the UK. Compare lunch takeaway vs home-cooked costs and save £1,200+ per year with batch-cooking tips.
Economics
Greggs Sausage Roll Inflation Rate Exposed
Uncover the Greggs sausage roll inflation rate and Sausage Roll Index UK. See how price hikes from £1.00 to £1.45+ reveal real purchasing power loss in 2026.
Construction & Roofing
How Many Roof Tiles Do I Need Per M²? Interlocking, Plain & Slate Guide
Calculate exact tiles per square metre. Compare interlocking concrete (9.5-10.5/m²), plain tiles (60/m²), and slates with pitch & gauge rules.
Education & Family
UK School Years by Age: Cut-Off Dates, Key Stages & Year Group Guide
Full breakdown of the 1 September cut-off date, Reception to Year 13, Key Stages 1-5, and summer-born deferral rights.
Personal Finance & Loans
Personal Loan Interest & APR in the UK: Monthly Repayments & Early Settlement
Understand daily reducing balance interest, the 51% Representative APR rule, and statutory early settlement rebates under the Consumer Credit Act.
Maternity & Health
How to Calculate Your Pregnancy Due Date: Naegele’s Rule & NHS Scans
Step-by-step Naegele 280-day calculations from LMP, cycle length adjustment matrices, IVF transfers, and NHS 12-week ultrasound rules.
Education & Higher Ed
UCAS Tariff Points Guide: How A-Levels, BTECs & T-Levels Convert
Master how A-Levels (16-56 pts), BTECs, T-Levels (168 pts), and EPQs convert into points, plus Russell Group entry requirements.
Health & Fitness
VO2 Max & Heart Rate Zones: What Your Cardio Score Means
Understand UK age & sex norms, Cooper 12-minute run formulas, Karvonen Zone 2 calculation, and Norwegian 4x4 intervals.
Health & Lifestyle
The 90-Minute Sleep Cycle Rule: Optimal Bedtimes & REM Stages
Calculate your exact bedtime for 6:00 AM, master NREM vs REM stages, and prevent morning sleep inertia.
Construction & DIY
Sand and Cement Render Mix Ratios UK Guide: Scratch & Top Coat
Master 4:1 base scratch coat vs 5:1 finish top coat proportions, plasticiser and waterproofer dosing, and 10m² bag coverage charts.
Education & Exams
GCSE Grade Boundaries Explained: 9 to 1 System & Mark Conversion
Understand how raw marks convert to 9–1 grades, Standard Pass (Grade 4) vs Strong Pass (Grade 5), and Results Day appeal rules.
Employment & Education
Term-Time Only Salary UK: How School Support Staff Pay is Calculated
Understand equated pay, 38 vs 39 weeks, INSET days, pro-rata holiday accrual, and 12 equal monthly instalments for teaching assistants.
Personal Finance
The 50/30/20 Budget Rule UK: How to Allocate Your Take-Home Pay
Allocate monthly net salary accurately: 50% essential needs, 30% discretionary wants, 20% savings & debt reduction, plus 60/20/20 adaptations for UK renters.
Motoring & Insurance
UK Car Insurance Groups Explained: Bands 1 to 50 & How to Lower Your Premium
Understand the 1–50 rating system by Thatcham & ABI, security suffix letters, cheapest Group 1 cars, the new 1–99 VRR scale, and 6 ways to cut premiums.
Motoring & Legal
UK Speeding Fines Explained: Band A, B, and C Penalties, Points & Court Limits
Understand UK speeding fines: Sentencing Council Band A, B, C percentages, penalty points vs disqualifications, £1,000/£2,500 statutory caps, and speed awareness course thresholds.
Cultural Metrology
Height in cm to Feet and Inches: Why the UK Measures People in Feet but Passports in cm
Convert height between metric and imperial: step-by-step cm to feet & inches math, average UK adult heights, and why NHS clinics and passports use metric while Britons use feet.
DIY & Construction
How much plasterboard do I need? UK sheet sizes & stud wall coverage guide
Calculate UK plasterboard sheets: 2400x1200mm vs 1800x900mm sizes, 400mm vs 600mm stud centres, 10-15% waste allowance, and drywall screws.
Tax & Motoring
HMRC mileage allowance rates 2026: The 45p vs 25p rule & claiming tax relief
Understand UK mileage rates: AMAP 45p/25p rules, claiming tax relief via Form P87, EV advisory electricity rates, and sole trader simplified expenses.
Employment & Law
Statutory annual leave entitlement UK: 28 days, bank holidays & pro-rata rules
Calculate UK holiday entitlement: 5.6 weeks statutory rules, the 28-day cap, bank holiday inclusion, part-time pro-rata, and 12.07% irregular hours accrual.
Family Finance
15 vs 30 hours free childcare UK: 2026 eligibility, dates & the £100k cliff edge
UK 30 hours free childcare 2026 guide: 9-month-old rollout, term-time vs stretched hours, Tax-Free Childcare stacking, and beating the £100k salary cliff edge.
Pensions & Retirement
How much pension do I need to retire in the UK? (The 4% rule & PLSA standards)
Calculate your retirement target: 2026 PLSA living standards, State Pension deductions, 4% safe withdrawal rate, and required private pension pot sizes.
UK Tax & Finance
Inheritance Tax UK: rules, 2026 thresholds and the 7-year gifting rule
Master UK inheritance tax: how the £325,000 allowance works, £175,000 property band, 7-year taper relief scale, and legal ways to protect family wealth.
Motoring & Finance
PCP vs HP car finance UK: balloon payments, voluntary termination & true costs
PCP vs HP compared: monthly savings, balloon payment risks, mileage penalty clauses, and why HP reaches the 50% voluntary termination point 14 months earlier.
Home Renovation
Skip sizes and prices UK: complete yardage & council permit guide
Which skip do you need? 2-yard to 14-yard dimensions, 2026 hire costs, council highway permit fees, and the critical 8-yard soil weight limit explained.
Kitchen Maths
Grams to millilitres: why flour, sugar and water are all different
Why 100g of flour isn't 100ml: how density works in baking, the 21% scoop error, and our free UK ingredient density chart.
Legal Metrology
Metric vs imperial in the UK: what’s legally required in 2026
Is imperial legal in the UK? Weights and Measures Act rules, the 4 statutory exemptions (beer, milk, bullion, road signs), and the 2023 consultation outcome.
DIY & Construction
Reading a tape measure: fractions, decimals and millimetres
Master UK dual tape measures: read 1/16th lines, decode the 2.375-inch mystery, convert fractions to mm, and why the end hook is loose.
Measurements
Why Britain still weighs itself in stone: history, law & body weight units
Why the UK stubbornly uses stone for body weight: the 1350 wool trade origins, Weights and Measures Act laws, stone vs lbs vs kg charts, and NHS rules.
Measurements
UK pint vs US pint: why British measures are 20% bigger
568ml Imperial pint vs 473ml US pint: 20 vs 16 fluid ounces, the fluid ounce paradox, Weights and Measures Act pub laws, and baking conversion traps.
Automotive & Cooking
Imperial vs US gallons: the difference that ruins recipes and MPG
Why the UK Imperial gallon is 20.1% larger (4.546L vs 3.785L), how it inflates UK MPG figures, the forgotten dry gallon, and food preservation hazards.
Automotive
Electric vs petrol: true cost of running a car in the UK (2026)
Real-world UK cost comparison: off-peak home charging (2.2p/mile) vs public DC rapid charging (20.8p/mile) vs petrol (16.2p/mile), plus tax and servicing.
Automotive
MPG explained: why UK and US figures don't match
Why UK MPG is 20.1% higher than US MPG: 4.546L Imperial gallon vs 3.785L US gallon, conversion factor 0.8327, WLTP vs EPA testing, and L/100km tables.
Health & Fitness
How many calories should I eat? UK NHS guidance and daily intake rules
Official NHS guidelines (2,000 kcal women, 2,500 kcal men), BMR vs TDEE formulas, safe 500-600 kcal deficit rules, and age-adjusted intake tables.
Health & Fitness
Daily water intake: how much do you actually need in the UK?
Complete UK guide to daily fluid requirements: NHS Eatwell Guide 6 to 8 glasses rule, what drinks count, caffeine myths, and urine hydration tests.
Construction
Loft insulation costs in the UK: 2026 prices, U-values, and grants
Full cost breakdown per m², Part L 270mm depth standards, cold vs warm roof setups, storage boarding, and Warm Homes funding.
Health & Fitness
BMI vs body fat percentage: which health metric actually matters?
Why BMI misclassifies athletes and normal-weight obesity, NICE waist-to-height ratio rules (<0.5), and US Navy formula calculations.
Finance
Salary sacrifice: how it works and when it’s worth it
Calculate Income Tax and NI savings on pensions and electric cars, avoid the 60% tax trap, and check mortgage rules.
Finance
Credit card minimum payments: why the balance never moves
Why minimum payments trap UK borrowers for 20+ years, the FCA persistent debt rules, and how fixed payments save £3,100+.
Construction
How much paint do I need? A room-by-room UK guide
Standard coverage per litre, deductions for doors and windows, mist coats on fresh plaster, and room-by-room tin sizes.
Construction
How much does a new roof cost in the UK? (2026 prices)
Full replacement prices for terraced, semi-detached and detached homes across concrete tiles, clay, slate, and flat roofing.
Construction
House extension cost UK: the full 2026 price guide
Cost per m² by spec, totals by size, cost by extension type, regional prices, fees, VAT and contingency.
Construction
Single-storey extension cost UK 2026
Price per m² by specification, total cost for 15–50 m², and how rear, side and wrap-around layouts compare.
Construction
Double-storey extension cost UK 2026
Two-storey price per m² of total floor area, 8-region cost table, 7 build stages, fees, VAT, and planning rules.
Construction
Kitchen extension cost UK 2026
Shell cost per m² plus kitchen fit-out, worked examples at 15m², 20m², and 30m², regional tables, and planning rules.
Construction
Side return & side extension cost UK 2026
Why a side return infill and a full side extension cost differently, with 2026 figures for each and the planning rules.
Construction
Does an extension add value? UK 2026
The uplift by room type, the £1.20–£1.50 per £1 rule, and how to work out your own value against the street ceiling price.
Construction
How much does fencing cost in the UK? 2026 prices per metre
Price per metre supplied and fitted, cost by fence type, per-panel prices, labour, old fence removal and the planning rules.
Construction
How much do fencing contractors charge in the UK? (2026 rates)
Day rate vs per-metre vs fixed price, what changes the cost, sole trader vs company, VAT, and how to compare quotes.
Construction
How much does it cost to fence a garden? (2026 UK prices)
Whole-project totals by garden size, a worked example, panel counts, labour, extras like a gate, and what changes the price.
Construction
Fence panel types and sizes: a UK buyer’s guide
Standard 6ft widths and 3ft–6ft heights, the 30mm continental post trap, feather edge vs lap, post sizing and planning rules.
Finance
Income Tax and National Insurance explained
How UK Income Tax bands and National Insurance actually work, with real examples of why take-home pay varies.
Finance
Stamp Duty Land Tax 2026: what you'll actually pay
How SDLT is banded, first-time buyer relief, the additional property surcharge, and when it's actually paid.
Finance
UK mortgage rates explained: fixed vs tracker vs variable
What each mortgage type actually means for your monthly payment, and how to use our repayment calculator to compare them.
Finance
ISA vs pension: where should your money go first?
How ISAs and pensions differ in tax treatment and access, and a simple framework for deciding where to save first.
Finance
Self-employed tax return: what sole traders actually owe
Income Tax, Class 2/4 National Insurance, allowable expenses, and why payments on account catch people out.
Finance
Statutory redundancy pay explained: how much you're owed
Who qualifies, how the age-banded formula works, and how statutory redundancy pay is taxed.
Finance
VAT for small businesses: a plain-English guide
When you need to register, how the rates work, and how to add or remove VAT from a price in seconds.
Construction
How much concrete do I need? A homeowner's guide
Working out volume, mix ratios and bag counts for a slab, post hole or path — before you order materials.
Automotive
UK Road Tax (VED) 2026: What You’ll Pay and Why
Complete 2026 guide: EV road tax changes, expensive car supplements (£50k threshold), first-year showroom rates, and the 3 registration eras explained.
Health & Fitness
BMI and healthy weight: what the NHS bands actually mean
The four NHS weight bands explained, why adjusted thresholds exist for some groups, and where BMI genuinely falls short.