Bike Gear Ratio Chart
Generate a full gear ratio chart for any chainring and cassette combination, shown as a color-coded matrix.
Get Weekly Training Tips
Join our newsletter for expert insights, training advice, and performance tips delivered to your inbox.
No spam, unsubscribe anytime. We respect your privacy.
Calculation Method
Bike Gear Ratio Chart: Read Your Whole Drivetrain
A gear ratio chart shows every chainring-and-cog combination on your bike as a single matrix, so you can see your easiest climbing gears and fastest top-end gears at a glance.
How Gear Ratios Work
Each ratio is the chainring teeth divided by the cog teeth. A 50-tooth chainring with a 25-tooth cog is a 2.0 ratio; with a 12-tooth cog it climbs to 4.17. Higher numbers are harder and faster, lower numbers are easier for climbing.
Reading the Matrix
Chainrings run down the left and cassette cogs across the top. Move along a row to see how the cassette changes your gear; move down a column to see the effect of switching chainrings. The color shading separates easy gears from hard ones so overlaps and gaps in your range stand out.
Why It Matters
Comparing charts for different chainring and cassette options is the quickest way to plan a build, spot redundant gears, and make sure you have a low enough gear for the climbs you ride.
Frequently Asked Questions
A gear ratio is the number of chainring teeth divided by the number of cog teeth. A 50-tooth chainring with a 25-tooth cog gives a 2.0 ratio, meaning the wheel turns twice for every full pedal revolution. Higher ratios are harder and faster; lower ratios are easier for climbing.
For steep climbs, riders want low ratios near or below 1.0, such as a 34-tooth chainring with a 32- or 34-tooth cog. These let you spin a comfortable cadence uphill without overloading your legs.
Chainrings run down the side and cassette cogs across the top. Each cell is that chainring divided by that cog. Reading across a row shows how gears change as you shift the cassette; reading down a column shows the effect of changing chainrings.
What is a gear ratio on a bike?
What gear ratio is best for climbing?
How do I read a gear ratio chart?
Related Calculators
Other helpful calculators for Cycling
Bike Gear Ratio Calculator
Calculate gear ratio, gear inches and chain angle of your bike based on the chainring and sprocket sizes.
Gear Inches Calculator
Calculate bicycle gear inches and development (meters of travel) from your chainring, cog, and wheel size. Compare gears across bikes and setups.
BMX Gear Calculator
Calculate your BMX gear ratio, gear inches, and rollout from chainring, sprocket, and wheel size.
Cycling Cadence Calculator
Calculate your pedaling cadence in RPM from your speed, gear ratio, and wheel size.