Two clearly different sections, with real variance in time estimates
The Monk's Trail to Doi Suthep splits into two clearly different sections: an easy 30 to 50 minute walk to Wat Pha Lat, then a much steeper, more demanding stretch onward to Doi Suthep itself that takes another 1 to 2 hours. Total one-way hiking time runs roughly 1.5 to 3 hours depending on your pace and which source you check, sources vary quite a bit on the exact numbers, so here's an honest breakdown rather than a single misleadingly precise figure.
A worthwhile hike on its own
This section is consistently described as easy to moderate. The trail covers roughly 2 to 2.4km one-way, gaining about 160m in elevation, mostly under forest canopy along a rocky path with a gentle incline. Multiple sources put the walking time at 30 to 50 minutes, and this section is well marked, look for orange monk robes tied around trees, and doesn't require a guide. It's scenic enough to work as a standalone outing if you're short on time or fitness, Wat Pha Lat itself, a small jungle temple with a stream and waterfall, is worth the trip on its own.
This is where the hike gets noticeably harder
This is where the hike gets noticeably harder. The trail becomes steep, in places climbing straight up without switchbacks, and can turn slippery or muddy after rain. Distance and time estimates vary more here than in Part 1, sources cite anywhere from 2.5 to 5km covering 45 minutes to 2 hours, reflecting real differences in hiking pace and how the trail is measured. Budget on the higher end of that range if you're not an experienced hiker, and expect ropes in a few of the steeper sections to help with the climb.
Sourced from inbetweentravels.com's Wat Pha Lat Monk's Trail guide, itsbetterinthailand.com's Monk's Trail hiking guide, veryhungrynomads.com's Monk's Trail hiking guide, thebackpackingfamily.com's Monk's Trail full route guide, and catisoutoftheoffice.com's ultimate Monk's Trail Doi Suthep guide.
No need to hike back down
The trail starts at the end of Suthep Road, just south of Chiang Mai Zoo, search "Wat Pha Lat" on Google Maps to find the exact spot. A Grab from the Old City takes roughly 15 to 20 minutes. There's no need to hike back down afterward, a red songthaew from Doi Suthep back to the city is a widely used option, and costs around 100 THB (RM13).
Start before 8am, both for the heat and the safety of company
Start early, ideally before 8am, both to avoid the heat and because this is when you'll see the most regular morning runners on the trail, which several reviewers note makes the path feel noticeably safer. Wear proper footwear, sections of the trail are rocky and uneven, and this isn't a hike to attempt in sandals. Bring bug spray, water, and something to cover your shoulders and knees before entering either temple complex. One reviewer also flagged an aggressive group of dogs near the top of the trail, worth being aware of, though this isn't universally reported.
Do the Wat Pha Lat section alone if you're short on time or fitness, it's a worthwhile hike on its own without needing to continue to Doi Suthep.
Start before 8am specifically if possible, the heat builds quickly once the sun is up, and the trail offers little shade in its steeper upper sections.
Take the songthaew back down rather than retracing your steps, most hikers use this option once they've reached the top, saving the return climb.
Check the season before planning your hike, November through April is consistently named the best window, given drier trail conditions and lower humidity.