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Tokyo, March

Tokyo Marathon Pacing Plan

Starts at the Tokyo Metropolitan Government Building in Shinjuku and runs a mostly out-and-back layout through the Imperial Palace area, Ginza, Asakusa's Sensoji Temple and Tokyo Tower before finishing near the Imperial Palace grounds. The course is fast and largely flat with a handful of gentle bridge crossings, and cool early-March temperatures make it one of the more record-friendly majors.

Distance

42.3 km

Elevation gain

+145m / -170m

Typically run in

March

Typical race-day weather

10°C, 14 km/h

Weather is a 10-year seasonal average for this course's location and month, not a forecast for a specific date — see FAQ.

Elevation profile

0km11km21km32km42km
Climbing effort zone (GAP raises target pace) Fade zone (modeled second-half slowdown, from 50%)

Sample strategy — 3:45:00 goal

A real, AI-generated excerpt of what Splitsmith produces for this exact course — not a hand-written example. Upload your own goal and recent results to get the full plan.

KM 0-5Km 1 drops on a -2.6% grade and clicks off at 4:37/km — resist reading that as free time banked, it's gravity, not fitness. Km 2 swings straight into a 2.3% climb and balloons to 5:59/km, so run this opening stretch by effort, letting the watch bounce rather than chasing either extreme. You cross 5K at 25:36, which is close to flat overall — treat it as your true baseline for the day.'

KM 6-15This stretch rolls gently with headwind hitting you on km 6, 10, 11 and 15, holding you in the 5:03-5:30/km band even though the grades are mild. Don't fight the wind kms individually — settle into rhythm and let the tailwind-friendly kms like 14 (5:01/km) even things out. You pass 10K at 52:06 and 15K at 1:18:11; both should feel controlled, not laboring.

KM 16-20Km 19 is the low point of this section — a 1.1% uphill grinds you down to 5:36/km, the slowest km so far — but km 20 flips to a -2.4% downhill with a tailwind and rewards you with 4:36/km. Don't get greedy on that downhill; let it happen, don't force a sprint. You cross the half around km 21 at roughly 1:49:54, a fair readout of where your 3:45 pace actually sits.

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Splitsmith is an independent pacing-plan tool and is not an official partner, sponsor, or affiliate of the Tokyo Marathon or its organizers. Course data source: digitized from the official course.

Tokyo Marathon Pacing Plan — Splitsmith