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BestBikeFit4U calculator

Gearing Calculator

Quickly understand your easiest and hardest gear, speed at your cadence, and whether your setup can handle the climb you have in mind.

1x and 2xFast and exactDashboard hand-off

Why this works

Exact gearing math, fast route check

The public calculator lays the groundwork. The dashboard later adds rider and event context.

Exact drivetrain math

Chainring, cassette, and wheel size convert straight into ratio, development, and speed.

Honest climb verdict

The tool does not pretend to know more than it does: the climb readout is a practical rule, not a power meter.

Clear upgrade direction

You can see right away whether a larger cassette, smaller inner ring, or wider 1x range makes more sense.

Build your setup

Use the chainring, cassette, and wheel circumference from your real bike. The tool gives exact gearing math and a simple climb-readiness readout.

Exact math, simple explanation

Gear ratio and speed are calculated exactly. The climb verdict is a practical ruleset based on gradient, band, and bike type.
High confidence

The defaults give you a useful starting point right away. Change them to your own setup for a more precise comparison.

Choose 1x or 2x.

This refines the climb-readiness verdict.

Pick the band closest to your route.

Choose a quick circumference estimate, then tweak it manually if needed.

For 1x, this is your only chainring.

T

The smaller ring determines your easiest gear.

T

Start with a known cassette, then fine-tune the cog sizes.

Use the smallest cog on your cassette.

T

This is your easiest gear for climbing.

T

Adjust this if you know your exact circumference.

mm

Use your usual climbing cadence.

rpm

The tool uses this to judge the easy gear against the climb.

%

Result

Your easiest and hardest gears, plus a quick climb-readiness readout.

Easiest gear

34 x 34

1.00x ratio · 26.4 gear inches

Hardest gear

50 x 11

4.54x ratio · 119.9 gear inches

Speed in easiest gear

10.1 km/h

At 80 rpm on a 8.0% climb.

Speed in hardest gear

45.9 km/h

Useful for seeing your top-end range on flatter roads.

Gear span

4.55x

The larger this is, the wider your spread from easiest to hardest gear.

Climb verdict

Challenging

Your easiest gear is close to the edge for a 8.0% climb. A smaller inner chainring would make this noticeably easier.

Explanation

Why this result changed

Confidence: High confidence

Next best action: Open the dashboard to compare this setup against your real bike setup.

Primary drivers

  • Chainring and cassette combination
  • Wheel circumference
  • Cadence

Secondary modifiers

  • Climb gradient
  • Climb length band
  • Bike type

Not covered here

  • Rider weight, FTP, and exact climb duration
  • Fatigue, wind, and altitude

What's next?

Compare this with your dashboard setup

Create a free account to compare this setup with your real bike and refine the climb verdict further.

The public version is for quick orientation. The dashboard goes further with rider, event, and climb demand.

Explore more

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