What is RiftUtils?
RiftUtils is a free, fan-made collection of League of Legends tools — CS calculator, armor & EHP math, objective timers, summoner-spell tracker, LP planner and a champion roulette.
Is it free?
Yes — completely free, no ads, no login required.
Does it send my data anywhere?
No. Every tool runs entirely in your browser. Nothing leaves your device.
Are the formulas accurate?
They mirror League's published formulas: damage reduction = R / (100 + R), cooldown reduction via haste = base × 100 / (100 + haste), and so on. If a value looks off, let us know.
Can I use it on mobile?
Yes. The layout adapts to any screen size.
How do I report a bug or suggest a feature?
Email hello@simonfoy.com or open an issue on GitHub.