How to Run a Half Marathon: A 12-Week Training Roadmap
6 min read ยท 2026-10-08
To run a half marathon, train for about twelve weeks with three to four runs per week, grow your long run gradually toward ten to twelve miles, keep most running easy, add one quality session per week and taper for the final ten days. If you can already run three miles comfortably, that timeline is realistic for most beginners.
This roadmap is a planning framework, not personalized coaching. It covers building a base, growing endurance, adding race-specific work, tapering and race day, along with how to stay consistent and adjust when you fall behind. If you have health concerns, check with a doctor before starting.
The roadmap at a glance
Goal: Finish a half marathon comfortably by following a gradual twelve-week training plan. Duration: 12 weeks
Base Building (Weeks 1-3)
Establish a regular running routine and comfortable aerobic base.
- Register for a half marathon about twelve weeks out to anchor your plan.
- Run three to four times per week at an easy, conversational pace.
- Build the weekly long run from around three to five miles.
- Add two short strength sessions focused on legs, hips and core.
- Track runs in an app like Strava, Garmin Connect or a simple training log.
Milestone: Three consistent weeks with a comfortable five-mile long run.
Endurance Growth (Weeks 4-7)
Extend the long run gradually while keeping recovery manageable.
- Increase the long run by about one mile per week with a lighter fourth week.
- Keep most weekly running at easy effort to protect recovery.
- Add strides or short pickups once a week to improve running form.
- Practice drinking and taking a gel or chew on runs over an hour.
- Test race-day shoes, socks and clothing on longer runs.
Milestone: A completed eight-mile long run with tested gear and fueling.
Race-Specific Work (Weeks 8-10)
Build confidence at the full distance and practice goal pacing.
- Reach a longest run of around ten to twelve miles.
- Add one weekly tempo run or goal-pace intervals.
- Include a few miles at goal race pace inside a long run.
- Rehearse race-morning breakfast and pre-run warm-up routines.
- Run a local 10K race or time trial to test pacing and logistics.
Milestone: A ten to twelve mile long run and a rehearsed race-day routine.
Taper and Race (Weeks 11-12)
Reduce volume to arrive fresh and execute a well-paced race.
- Cut weekly mileage gradually while keeping a few short goal-pace efforts.
- Avoid new shoes, foods or workouts in the final two weeks.
- Review the course map, aid stations and start logistics.
- Start the race slightly slower than goal pace for the first two miles.
- Take several easy days after the race before planning your next goal.
Milestone: Crossing the half marathon finish line with an even, controlled pace.
What a Typical Training Week Looks Like
A simple half marathon week includes three or four runs, one or two strength sessions and at least one full rest day. A common structure is an easy run early in the week, a quality session midweek such as strides or a tempo run, another easy run and a long run on the weekend. Rest or cross-training fills the other days.
Keep the structure consistent so training becomes a habit rather than a daily decision. Schedule runs in your calendar like meetings. If your week is unpredictable, prioritize the long run first, then the quality session, then easy runs. Missing one easy run matters far less than repeatedly skipping long runs.
- Monday: rest or easy cross-training.
- Tuesday: easy run plus strides.
- Wednesday: strength training.
- Thursday: tempo or goal-pace run.
- Saturday or Sunday: long run at easy effort.
Finding Your Goal Pace
For a first half marathon, finishing comfortably is a great goal on its own. If you want a time target, use a recent 5K or 10K result with an online race equivalency calculator to estimate a realistic half marathon pace. Treat the estimate as a starting point and adjust based on how training runs feel.
Practice goal pace in small doses during tempo runs and long runs so your body learns the rhythm. On race day, aim to run the first couple of miles slightly slower than goal pace, settle in through the middle miles and save any push for the final stretch. Running even splits is usually more comfortable than fading badly after a fast start.
Staying Consistent When Life Gets Busy
Twelve weeks is short enough that a few missed sessions can feel stressful. The key is not letting one missed run turn into a missed week. If you skip a run, simply move on to the next scheduled session rather than cramming. If you miss a long run, do a slightly shorter version later in the week if your schedule allows.
Morning runs are easier to protect for many people because fewer things compete for that time. Lay out clothes the night before, plan routes in advance and consider a running buddy or club for accountability. Tracking runs visually, such as with a calendar or app streak, also helps you see progress and stay motivated.
What to Do If You Fall Behind
If illness, travel or a busy stretch costs you a week or more, step back rather than jumping straight to the planned long run. Repeat your last completed week, then continue progressing. You can shorten the taper slightly or reduce your peak long run if time is tight. Finishing healthy matters more than hitting every planned mile.
If you fall far behind, consider adjusting the goal rather than forcing it. Run the race with planned walk breaks, aim purely to finish or switch to a later race. Persistent pain is a reason to rest and seek advice from a qualified professional, not to push harder.
Common mistakes to avoid
- Running every run fast; keep most runs easy and limit hard efforts to one session per week.
- Making up missed runs by doubling up; skip the missed session and continue with your plan.
- Jumping long-run distance too quickly; add about a mile per week with regular lighter weeks.
- Trying a new gel or new shoes on race day; test everything during training long runs.
- Going out too fast at the start; run the first two miles slightly slower than goal pace.
- Skipping rest days; schedule at least one full rest day weekly to recover and adapt.
Frequently asked questions
How long does it take to train for a half marathon?
Many beginner plans run about ten to fourteen weeks, assuming you can already run around three miles comfortably. If you are starting from zero, add a few weeks of walk-run training first to build a base. A twelve-week plan is a common middle ground that leaves room for a few missed sessions.
How far should my longest training run be?
Most beginner half marathon plans peak with a long run of around ten to twelve miles. Running the full 13.1 miles in training is not required. Rested legs, the taper and race-day energy usually carry you through the final miles comfortably if your training has been consistent.
Can I walk during a half marathon?
Yes. Walking is common in half marathons, and planned walk breaks can help beginners finish feeling stronger. If you plan to use a run-walk method, practice it on long runs so it feels natural on race day, and check the race time limit to make sure your expected pace fits within it.
What should I eat before a half marathon?
Eat a familiar breakfast that you have tested before long training runs, typically a few hours before the start. Choose foods that sit well with you and avoid trying anything new. For specific dietary needs or medical conditions, check with a qualified professional for advice tailored to you.
How many days a week should I run for a half marathon?
Three to four running days per week is enough for most beginners. That schedule allows a long run, an easier recovery run, a quality session and rest days for recovery. More experienced runners may run more often, but adding days too quickly can increase fatigue and make consistency harder.