Ever stood at the start of a walk wondering, How long is this actually going to take me? Same.Whether you're heading out for a quick wander with the kids or a big leg-burner in the hills, having a rough idea of how long your hike will take can make all the difference - especially when you're chasing views and daylight.This handy little calculator is based on Naismiths Rule, a well-known way to estimate hiking time using distance and elevation. And if you hike at a different pace (we all do!), Ive added an option to adjust for that too - whether youre in slow-plod mode or powering up like a mountain goat. Estimated Hiking Time (Naismiths Rule)This first version of the calculator uses the classic Naismiths Rule:1 hour for every 5km (3 miles), plus 1 hour for every 600m (2,000ft) of ascentSo, if youre doing a 10km route with 600m of elevation gain, youre looking at about 2 hours hiking time.Use the calculator below to try it out for your next route: Estimated Hiking Time (Naismith's Rule) Distance (km): Total Ascent (metres): Calculate Time Naismith's Rule Calculator (Simplified) Distance (km): Total Ascent (metres): Calculate Estimated Hiking Time with Intended PaceLets be honest - not all of us hike at the same speed. Some days its a toddler-paced stroll with snack stops every 10 minutes (been there), and other days its a fast solo mission to the summit.This version lets you choose your intended pace (Slow, Normal, Fast, or Run) and itll give you a more personalised estimate based on minutes per mile (converted to km behind the scenes):Slow: 45 mins per mile (hello, relaxed rambles)Normal: 37 mins per mileFast: 29 mins per mileRun: 21 mins per mile (trail runners, this ones for you!)Just pop in your route details and pace to see your tailored hiking time: Estimated Hiking Time with Intended Pace Distance (km): Total Ascent (metres): Intended Pace: Slow (45 mins per mile) Normal (37 mins per mile) Fast (29 mins per mile) Run (21 mins per mile) Calculate Time What is Naismiths Rule?Naismiths Rule was created back in 1892 by a Scottish mountaineer called William W. Naismith. His aim? To help people estimate how long a route would take based on distance and how much uphill was involved.The formula is pretty straightforward:1 hour per 5km (3 miles) on flat groundAdd 1 hour per 600m (2,000ft) of ascentIts brilliant for rough planning, especially in the mountains but keep in mind, it doesnt account for terrain (think bogs, scrambles or scree), fitness levels, or breaks for snacks, nappies, or a well-earned summit sit-down. How Accurate is Naismiths Rule?In short: its a decent estimate, but not perfect.Naismiths Rule is great for giving you a ballpark figure, especially if youre doing hill walks or longer routes. But it assumes a steady pace on decent terrain - which, lets face it, isn't always real life.Heres when it might be less accurate:The ground is steep, rocky, or boggyYoure walking with kids (hi, fellow hiking parents!)Youre stopping often for photos, snacks, or just to enjoy the viewYoure particularly speedy or taking it super steadyThats why the intended pace option above can help tweak the estimate to match your kind of hiking. Knowing roughly how long your hike will take is a simple but powerful thing. It helps you plan better, pack right, and stay safe especially in places where weather, light, or little legs can make a big difference.So whether you're heading out for an early morning solo hike or a laid-back loop with the family, give the calculator a go and let it take a bit of guesswork out of your next adventure.And remember: theres no rush in the mountains. Its not a race its a wander.