Training
How Long to Train for a Half Marathon (Honest Timelines by Starting Point)
How long to train for a half marathon depends on where you start: 10–14 weeks if you can run a 5K comfortably today, 8–12 weeks from a solid 10K base, and 16–20 weeks from the couch. The timeline that hurts people is the aggressive one — 13.1 miles punishes rushed builds with injuries at exactly the moment training was starting to work.
Timelines by starting point
- From the couch: 16–20 weeks. Spend the first 8 weeks getting to a comfortable 5K (here’s that path), then start the half build. Skipping the base phase is how shin splints happen.
- From a comfortable 5K: 10–14 weeks. The sweet spot most plans target. Runner’s World’s beginner guidance and the classic novice plans both live in this window.
- From a recent 10K: 8–12 weeks. You’re one long-run build away — the 10K-to-half jump has its own article.
Real runners confirm the math: r/running’s consensus for beginners lands at three to four months, with the couch-first crowd closer to five.
The weekly shape (it’s simpler than the apps make it)
- Two easy runs of 30–45 minutes at conversational pace
- One long run that grows by about a mile a week
- Every third or fourth week holds flat — consolidation is the adaptation
- Peak long run of 10–12 miles, two to three weeks out
- A two-week taper you don’t negotiate with
Pick the race first
A half marathon on the calendar turns a vague ambition into a training block. Count back from race day: if it’s 12 weeks out and you have a 5K base, you’re on time. Halfs are listed in every metro — find yours, filter to half marathon, and note that fall is when the good ones cluster (October is the biggest race month in America). Use the pace chart to translate your easy pace into an honest first-half target, then plan the middle miles with even splits.
Quick answers
How long does it take to train for a half marathon as a beginner?
If you can run a 5K comfortably today, plan 10-14 weeks. If you're starting from zero, plan 16-20 weeks: roughly 8 weeks to a solid 5K, then the half build on top. Rushing the timeline is the most common cause of injury in first-half training.
How many runs per week do you need for half marathon training?
Three quality runs per week is enough for a first half marathon: two easy 30-45 minute runs and one long run that grows weekly. More runs help experienced runners; beginners get more from rest than from a fourth run.
What's the longest run before a half marathon?
Most beginner plans peak at 10-12 miles two to three weeks before race day. You don't need to run 13.1 in training — race-day adrenaline, crowds, and taper freshness reliably carry you the final miles.
Published 2026-07-21 · RunFinders