Tools
Free charity calculators
Every tool is free to use and free to embed on your own site — the embed includes a credit link back to CharityCompare, which is how they stay free.
Donations
Gift Aid Calculator
What your donation is worth to a charity (25% top-up), what you reclaim at 40% or 45%, and a reverse mode for what you can afford to give.
Open the calculator →Compare schemes
Payroll Giving vs Gift Aid
Side-by-side comparison of both giving schemes at your tax band — charity value, net cost, and the verdict for your situation.
Open the calculator →Higher earners
Personal Allowance Optimiser
Earn £100k–£125,140? See the exact donation that restores your full Personal Allowance — up to 60% effective relief.
Open the calculator →Faith giving
Zakat Calculator
Hanafi 2.5% on net assets above the silver nisab. You enter today’s silver price, so the threshold is never a stale figure.
Open the calculator →