Weather
Climate Avg| Time | Temp | Dew Pt | Humidity | Wind | Conditions |
|---|---|---|---|---|---|
| Start | 41.7 – 41.7°F | 41° Ideal | 97 – 97% | 3 mph NE | Partly cloudy |
| 8:00 AM | 43.1 – 43.1°F | 41° Ideal | 92 – 92% | 3 mph E | Partly cloudy |
| 9:00 AM | 46 – 64°F | 47° Ideal | 67 – 95% | 5 mph S | Partly cloudy |
| 10:00 AM | 49 – 67.6°F | 51° Nice | 63 – 95% | 6 mph SW | Rain |
| 11:00 AM | 49.1 – 71.1°F | 52° Nice | 59 – 97% | 7 mph SW | Rain |
| Finish | 52.2 – 74.1°F | 53° Nice | 54 – 89% | 8 mph SW | Drizzle |
Based on 3-year average for this date. Real forecast available in 261 days.
Elevation Profile
Course Stats
Course Breakdown
Hopkinton Descent
Run 20-30 seconds per mile slower than your flat pace. Bank leg freshness, not time.
The opening miles drop sharply out of Hopkinton. It feels effortless, which is the trap. The eccentric loading on your quads starts here and compounds through mile 20. Every second you bank on the downhill costs you double on the Newton hills.
The Rolling Middle
Find your rhythm. This is where your race pace should feel comfortable, almost easy.
The course flattens out through Ashland, Framingham, and Natick. These miles are about settling in and staying disciplined. The crowds thin between towns but pick up as you approach Wellesley. Mile 13 is the Scream Tunnel, a wall of noise that tempts runners into surging.
Newton Hills
Maintain effort, not pace. Let your splits slow and spend your pace bank here.
Four distinct climbs between miles 16 and 21, culminating in Heartbreak Hill at mile 20.5. Heartbreak isn't the steepest hill on the course, but it hits after 16 miles of quad-punishing downhill and three prior climbs. The goal is to arrive here with legs and pace bank intact.
Boylston Street
Descend carefully off the hills, then hold whatever pace you have left into the finish.
The course drops from Boston College back toward sea level, then flattens for the final push along Beacon Street into downtown. The Citgo sign at mile 24.5 is your landmark. The last mile is flat along Boylston Street with the finish line in sight.
Mile Splits
| Mile | Grade |
|---|---|
| 1 | -1.9% |
| 2 | -1.0% |
| 3 | -1.2% |
| 4 | -1.1% |
| 5 | +0.4% |
| 6 | -0.4% |
| 7 | -0.3% |
| 8 | +0.0% |
| 9 | -0.3% |
| 10 | +0.4% |
| 11 | +0.5% |
| 12 | -0.9% |
| 13 | -0.1% |
| 14 | +0.0% |
| 15 | +0.4% |
| 16 | -2.2% |
| 17 | +1.2% |
| 18 | +0.7% |
| 19 | -0.6% |
| 20 | +0.5% |
| 21 | +1.7% |
| 22 | -1.5% |
| 23 | -0.9% |
| 24 | -1.0% |
| 25 | -0.6% |
| 26 | +0.0% |
| 27 | -0.2% |
RM Difficulty Index
Race-Day Weather History
Race-morning conditions on this date over the past 7 years: median 45°F with a 39°F dew point and 7 mph wind. Heat has rarely been a factor.
| Year | Temp | Dew Pt | Wind | Rain | Sky |
|---|---|---|---|---|---|
| 2025 | 62°F | 51°F | 11 mph | — | Partly cloudy |
| 2024 | 45°F | 40°F | 4 mph | — | Partly cloudy |
| 2023 | 43°F | 26°F | 10 mph | — | Partly cloudy |
| 2022 | 50°F | 50°F | 13 mph | 0.17" | Rain |
| 2021 | 51°F | 39°F | 3 mph | — | Partly cloudy |
| 2020 | 40°F | 29°F | 7 mph | — | Partly cloudy |
| 2017 | 42°F | 32°F | 6 mph | — | Partly cloudy |
Morning conditions (race window) on the Boston Marathon calendar date each year, from the ERA5 reanalysis archive — the race’s usual slot, not necessarily each edition’s exact day.
Boston Marathon Pace Calculator: 26.2 Miles of Splits & Race Plan
The Boston Marathon is 26.2 miles (42.195 km), the standard marathon distance, running point-to-point from Hopkinton to Boylston Street in downtown Boston. The course drops 460 feet in the first half and then climbs 300 feet through the Newton hills between miles 16 and 21. Most runners blow up here because they bank too much time on the downhills and pay for it later. Your quads take real damage on those early descents, and by the time you hit Heartbreak Hill at mile 20.5, you're running on borrowed legs.
The fastest time ever recorded at Boston is 2:03:02, run by Geoffrey Mutai in 2011 with a strong tailwind (not ratifiable as a world record due to the point-to-point course and wind assistance). The men's fastest official winning time is 2:04:45 by John Korir (2025), while Sharon Lokedi smashed the women's course record with 2:17:22 in 2025, breaking Buzunesh Deba's 2:19:59 from 2014. Our pace model accounts for the downhill quad damage, the cumulative fatigue at each Newton hill, and the typical April weather in Boston, which can swing from 40 to 75 degrees. The splits model how your body actually responds to every mile of this specific terrain.
Boston Marathon FAQ
When is the next Boston Marathon?›
The next Boston Marathon is on Monday, April 19, 2027.
How long is the Boston Marathon?›
The Boston Marathon is 26.2 miles (42.195 km), the standard marathon distance. It runs in Hopkinton to Boston, MA.
How much elevation gain does the Boston Marathon have?›
The Boston Marathon has about 585 ft (178 m) of climbing and 1,024 ft of descent, with a maximum grade of 9.6%.
Is the Boston Marathon flat, downhill, or hilly?›
The Boston Marathon is a net downhill course, dropping 440 ft (134 m) from start to finish, with 585 ft of climbing along the way.
How hard is the Boston Marathon?›
Runner's Math scores the Boston Marathon 26/100 (Moderate) — #31 of 38 marathon courses in our library, ranked by modeled time cost. The profile costs about 0:11 versus a flat course for a runner at 4:00-marathon pace.
What's the weather usually like at the Boston Marathon?›
Over the past 7 years on this date, median race-morning conditions were 45°F with a 39°F dew point and 7 mph wind. Heat has rarely been a factor.