About · Aerix

About Aerix

Aerix is a comprehensive suite of running tools designed to empower runners of all levels to achieve their goals. Whether you are training for your first 5K or aiming to qualify for the Boston Marathon, our accurate calculators and data-driven insights help you train smarter and run faster. Our mission is to simplify the complex mathematics of running training. We believe that every runner deserves access to professional-grade tools to optimize their performance. From calculating the perfect race pace to determining your heart rate training zones, Aerix provides the precision you need. We are constantly evolving and adding new features based on feedback from the running community. Our team is passionate about running and technology, and we are dedicated to building the best possible experience for our users.

23K+

RUNNERS

CALCULATORS

240+

GLOSSARY

Principles · What We Believe

Our Approach to Accuracy

We take formula accuracy seriously. Every calculator on Aerix is built on published, peer-reviewed research: • Race Predictor: Uses the Riegel formula (Peter Riegel, 1977), the industry-standard model for equivalent race performance prediction across distances. • Heart Rate Zones: Implements the Karvonen method (Martti Karvonen, 1957), which uses heart rate reserve for personalized, physiologically meaningful training zones. • Calorie Calculator: Uses MET (Metabolic Equivalent of Task) values sourced from the ACSM (American College of Sports Medicine) Compendium of Physical Activities. • VO2 Max Estimator: Based on the Jack Daniels VDOT formula, widely used by coaches and exercise physiologists worldwide. • Pace Calculator: Standard pace-distance-time relationships with support for both metric and imperial units. We document our methodology in the Resources section so you can verify the math yourself. Transparency is part of how we build trust with our users.

Our Mission

To provide accessible, accurate, and easy-to-use tools that help runners worldwide reach their full potential.

For Runners, By Runners

Aerix is built for runners at every stage of the journey — from someone lacing up for their first run to an experienced athlete chasing a Boston Qualifier. We believe running is a universal sport, so Aerix is available in four languages: English, Korean (한국어), Japanese (日本語), and German (Deutsch). All translations are reviewed for natural readability, not just literal accuracy, so every runner gets the same quality experience regardless of their language. Whether you are training solo, part of a running club, or coaching a group, our tools are designed to be simple enough for beginners and precise enough for advanced athletes. There are no tiers, no restrictions — just the tools, open to everyone.

Who We Are

Aerix was founded by a software engineer who is also a dedicated long-distance runner. After years of juggling spreadsheets, outdated apps, and paywalled tools just to plan a training week, the decision was made to build something better from scratch. With over a decade of personal running experience — spanning everything from local 5Ks to full marathon training blocks — the tools on this site are built with a runner's real needs in mind, not just as theoretical exercises. Every calculator, every formula, and every training plan template has been validated against real training data and peer-reviewed sports science. Aerix is an independent project, not backed by a corporation or venture capital. That independence means the focus stays entirely on what runners actually need: clean, fast, accurate tools with no upsells, no account walls, and no distractions.

Why We Built Aerix

Most free running calculators on the internet fall into one of three traps: they are buried under intrusive ads, they use outdated or imprecise formulas, or they hide the most useful features behind a subscription paywall. Aerix was built to be the exception. Every tool on this platform is: • 100% free — no account required, no premium tier, no upsells • Ad-light — we keep the experience clean and focused on the content • Scientifically grounded — all formulas are sourced from peer-reviewed research and established sports science standards • Fast and mobile-friendly — built for runners who check their phone between intervals, not just at a desktop We believe serious training tools should be available to every runner, not just those who can afford a coaching subscription.

What We Offer

Aerix provides seven calculators and a growing library of training resources: • Pace Calculator — Convert between pace, speed, distance, and time. Supports km and miles. • Race Predictor — Predict your finish time at any distance based on a recent race result using the Riegel formula. • Heart Rate Zones — Calculate your five training zones using the Karvonen method and your resting heart rate. • VO2 Max Calculator — Estimate your aerobic capacity from race performance data. • Calorie Calculator — Estimate calories burned during a run based on your weight, distance, and pace. • Treadmill Calculator — Convert treadmill speed and incline settings to outdoor equivalent pace. • Unit Converter — Instantly convert between km/mi, kg/lb, and other running-relevant units. Beyond calculators, we offer structured training plans for distances from 5K to marathon, an in-depth running glossary covering training terminology, race jargon, and equipment, and a growing wiki of running guides and legends profiles.

Get in Touch

We love hearing from runners. Whether you have found a bug, have a suggestion for a new feature, or just want to share a race result — reach out. Email us at contact@runaerix.com and we will get back to you as soon as possible. Feedback from the community is one of the most important drivers of how Aerix evolves, so no message is too small.

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