How do I know when brake pads need replacing?

Disc brake pads: check thickness, replace when less than 1mm of compound remains. Rim brakes: replace when the wear indicator grooves disappear. Never ride with worn-out brake pads.

Resin vs sintered disc pads?

Resin (organic) pads offer better modulation and are quieter, but wear faster. Sintered (metallic) pads last longer, work better in wet/mud, but can be noisier and need more force initially.

Do rim brakes wear the rim?

Yes. Carbon rims wear brake pads very fast and need specific pads. Aluminium rims gradually wear from rim braking. Check for a wear indicator groove or concave brake track.

Why do pads wear faster in the wet?

Water and grit create an abrasive slurry that rapidly wears brake pads (and rims for rim brakes). Wet winter riding can halve pad life compared to dry summer riding.

Should I replace front and rear pads together?

Not necessarily. Rear pads often wear faster (many riders brake more with the rear). Check both regularly and replace independently when needed.

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Brake Pad Calculator — Estimate Brake Pad Life

Estimate brake pad life based on riding conditions, terrain and rider weight.

Weekly Riding Distance

Average distance you ride per week, including commuting and leisure — used to convert pad life in km into months

Rider Weight

Your body weight — heavier riders need more braking force, so pads (and rims) wear faster

Brake TypeResin/organic disc pads bite well and are quiet but wear fastest; sintered/metallic last longest and shed wet and mud; rim pads sit in between (carbon rims chew pads far faster than alloy)

TerrainMore descending means more braking — flat roads extend pad life, while hilly and mountainous riding wear pads much faster

How We Calculate This

Brake Pad Life Estimation

Base life: Rim ~3000 km, Disc resin ~2000 km, Disc sintered ~4000 km (mixed terrain, ~75 kg rider). These sit within published ranges: resin disc ≈ 800–2400 km, sintered disc ≈ 1600–4800+ km, rim ≈ 800–4000 km.
Terrain: Flat (+50%), Mixed (baseline), Hilly (−40%), Mountain (−60%)
Weight: Under 60 kg (+20%), 60–80 kg (baseline), 80–90 kg (−15%), Over 90 kg (−25%)
Pad life = Base × Terrain × Weight multiplier
Months to replacement = Pad life ÷ monthly distance (weekly distance × 52 ÷ 12)

These figures are rough heuristics, not precise wear measurements. Real-world pad life varies 2–4× with weather, braking technique and front/rear bias — wet, gritty winter riding can roughly halve pad life, and dragging the brakes downhill wears pads far faster than firm, intermittent braking. Use the result as a service-interval guide, not a guarantee, and inspect pads regularly: replace disc pads when under ~1 mm of compound remains, and rim pads when the wear-indicator grooves disappear. You can override any base figure in Advanced Options if you know your own real-world pad life.

Frequently Asked Questions

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Last updated: February 2026

All calculations are estimates. Always verify results and consult a professional bike fitter where appropriate.