ModelCalcs.uk
Budget Calculator — Annual Hobby Spending Planner
Plan your annual hobby budget across kits, paints, tools and events to keep spending on track.
How We Calculate This
Removes any savings set-aside first, splits the remaining (spendable) monthly budget across categories using your percentages, then projects the annual totals — optionally uplifted for inflation.
Formula
- Spendable monthly = Monthly budget × (1 − Savings% ÷ 100)
- Category monthly = Spendable monthly × (Category% ÷ 100)
- Category annual = Category monthly × 12 × (1 + Inflation% ÷ 100)
- Annual budget = Spendable monthly × 12 × (1 + Inflation% ÷ 100)
With the defaults (0% savings, 0% inflation) the spendable budget equals your monthly budget, the inflation factor is 1, and the five category annual lines sum exactly to the headline Annual budget.
Frequently Asked Questions
Related Calculators
Project Cost Calculator
Estimate total project cost including kit, paints, tools and aftermarket parts.
Build Time Calculator
Estimate total build hours based on complexity, experience and sessions per week.
Collection Value Calculator
Track and estimate the value of your model collection for insurance or sale.
Display Case Calculator
Calculate display case dimensions and shelf spacing for your collection.
Shipping Calculator
Estimate box size, packing materials and weight for shipping models safely.
Was this calculator helpful?
Last updated: February 2026
All calculations are estimates. Always verify quantities before purchasing materials.