London, April
TCS London Marathon Pacing Plan
Three separate start points near Blackheath and Greenwich Park converge by 3 miles, then the route follows the Thames past Cutty Sark, through Docklands and the Isle of Dogs, over Tower Bridge around the halfway point, and along the Embankment to finish on The Mall. The course is gently rolling rather than pancake-flat — small rises through Greenwich and Charlton in the first miles, then largely flat riverside running from halfway on.
Distance
26.3 mi
Elevation gain
+48m / -83m
Typically run in
April
Typical race-day weather
9°C, 8 mph
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
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 1-4 — The opening kilometers are gently rolling with a tailwind at your back, and the field will surge — resist it. Run 5:24-5:19/km through km3, a shade slower than your 5:19/km goal pace, then let the tailwind and the -0.7% grade carry you to 5:05/km by km4 without forcing it. You cross km4 at 21:08; that's fine, but don't treat the free speed as a new baseline for the rest of the race.
KM 5-8 — Km5 drops -2.6% with the wind still helpful, producing an easy 4:35/km — bank the terrain, not extra effort. From km6 a headwind sets in and holds through km8, so even as the route flattens your pace naturally settles to 5:05-5:16/km. You hit km8 at 41:17; if you're much ahead of that, you spent km5 wrong.
KM 9-20 — This is the long, quietly attritional middle: a persistent headwind (per the 10-year seasonal average, roughly 12.4 kph) sits on you almost the whole way, and the terrain is only gently rolling, so splits drift between 5:12 and 5:24/km even though it feels like effort is climbing. Use the checkpoints to stay honest — 10K at 52:01, 15K at 1:18:33 — and expect km20 to read 5:31/km, the slowest split yet, from the combined 0.8% uphill and headwind. That's the course, not a fade — don't panic and don't chase it back.
Build your TCS London Marathon plan
Upload your own GPX or use TCS London Marathon's course — set your goal and recent results, and get the full km-by-km strategy.
Build my TCS London Marathon plan →Splitsmith is an independent pacing-plan tool and is not an official partner, sponsor, or affiliate of the TCS London Marathon or its organizers. Course data source: digitized from the official course.