# How Steep Is a 42% Treadmill Incline? A Real-World Grade Comparison **By The A-Team · Published August 24, 2026 · Updated August 25, 2026** A 42% treadmill incline is a 22.8 degree climb, which means you gain 42 feet of elevation for every 100 feet you travel forward. That is steeper than Baldwin Street in New Zealand, the steepest street on earth, and it sits just under the average grade of Colorado's Manitou Incline. It is a hiking grade, not a running grade. Most home treadmills stop at 15%. A few reach 18%. So when a spec sheet says 42%, it is fair to wonder whether that number means anything in the real world, or whether it is just a bigger number to put on a box. Here is what it actually looks like when you stand on it. --- ## In This Article - [What does a 42% incline actually mean?](https://www.avironactive.com/blog/how-steep-is-42-percent-treadmill-incline/#meaning) - [How does 42% compare to real-world hills?](https://www.avironactive.com/blog/how-steep-is-42-percent-treadmill-incline/#compare) - [How much climbing is that in 30 minutes?](https://www.avironactive.com/blog/how-steep-is-42-percent-treadmill-incline/#climbing) - [Can you actually run at 42%?](https://www.avironactive.com/blog/how-steep-is-42-percent-treadmill-incline/#running) - [What incline should you actually use?](https://www.avironactive.com/blog/how-steep-is-42-percent-treadmill-incline/#useful) - [Which Aviron treadmill goes to 42%?](https://www.avironactive.com/blog/how-steep-is-42-percent-treadmill-incline/#which) - [Frequently asked questions](https://www.avironactive.com/blog/how-steep-is-42-percent-treadmill-incline/#faq) --- ## What Does a 42% Incline Actually Mean? Treadmill incline is measured as **grade**, not angle, and the two are not the same number. Grade is rise divided by run, expressed as a percentage. Climb 42 feet over 100 feet of forward travel and you are on a 42% grade. Converted to an angle, that is 22.8 degrees. The gap between those two numbers is where most of the confusion lives. People hear "42%" and picture something close to halfway to vertical, because 42% sounds like it should be almost half of 90 degrees. It is not. A 100% grade is 45 degrees, and a vertical wall has no grade at all, because the run is zero. So 22.8 degrees is the honest answer. That is still very steep. It is steeper than any street you have legally driven on, and steeper than the black diamond threshold at most North American ski resorts, which starts around 40%. --- ## How Does 42% Compare to Real-World Hills? Numbers on a spec sheet are abstract. Streets and trails are not. Here is where 42% lands against grades you can actually go stand on. | Grade | Angle | Where You Find It | |-------|-------|-------------------| | 8.33% | 4.8° | Steepest slope allowed on an ADA wheelchair ramp | | 12% | 6.8° | The incline in the 12-3-30 workout | | 15% | 8.5° | The ceiling on most home treadmills | | 18% | 10.2° | A well-specified performance treadmill | | 31.5% | 17.5° | Filbert Street, San Francisco | | 34.8% | 19.2° | Baldwin Street, New Zealand — the world's steepest street | | 41% | 22.3° | Bradford Street, the steepest in San Francisco | | 42% | 22.8° | Aviron Summit, maximum incline | | 45% | 24.2° | Manitou Incline, Colorado — average grade | | 68% | 34.2° | Manitou Incline, steepest section | Two things jump out. First, 42% is steeper than Baldwin Street, which Guinness World Records lists at 34.8%. Second, it is roughly five times the maximum slope the US Access Board permits on a wheelchair ramp. You are not walking up a ramp. You are walking up a trail. --- ## How Much Climbing Is That in 30 Minutes? This is where the number stops being trivia. Walk at a modest 2 mph at 42% for 30 minutes and you cover one mile of belt. Because the belt is tilted at 22.8 degrees, that mile translates to roughly **2,045 feet of vertical gain**. For reference, the Manitou Incline gains 2,011 feet. People fly to Colorado to do that once and talk about it for a year. Thirty minutes of steady walking at 42% is the same climb, in your living room, in shoes you did not have to break in. Push to 3 mph and the same half hour becomes about 3,067 feet. That is the part most people underestimate: at a steep enough grade, walking is the hard workout. You do not need speed, and your knees do not need the pounding that comes with it. --- **Aviron Summit Treadmill** — The incline specialist ![Aviron Summit incline trainer treadmill](https://cdn.builder.io/api/v1/image/assets%2F45e65c713405486e8fe2ec324b61c21f%2F52d0791d89384b5685dbc221c2938dc3?format=webp&width=240&height=240&fit=cover) Climbs to 42% and drops to a 6% decline, with hiking handles and a 22 inch by 61 inch deck. The steepest incline range in the category. 30-day risk-free trial. Financing available. [Aviron Summit Treadmill] : https://www.avironactive.com/shop/aviron-summit-treadmill/ --- ## Can You Actually Run at 42%? No, and no treadmill worth trusting will let you try. On the Summit, the 14 mph top speed applies at inclines up to 15%. Past that, the machine limits speed on purpose, because running at 22.8 degrees is not a workout — it is a fall waiting to happen. Steep grades are a **walking** tool. That is the point of them. Incline walking gets your heart rate into a hard zone while your feet stay in contact with the belt, which keeps impact low. It is the same trade that makes hiking feel easier on the body than road running, even when it leaves you more tired. This is also why the Summit has hiking handles with incline and speed keys built in. At a genuine trail grade, you want something to hold, and you want to change the grade without reaching for a screen. --- ## What Incline Should You Actually Use? A ceiling is not a set point. Here is a more useful way to think about the range: - **1% to 3%:** The everyday baseline. A slight grade offsets the fact that a belt does some of the work for you. - **10% to 12%:** The 12-3-30 zone. Hard enough to matter, sustainable for 30 minutes. - **15% to 20%:** Real hill work. Most treadmills tap out somewhere in here. - **25% to 42%:** Intervals, not steady state. Two to five minutes at a time, then bring it back down. - **Decline:** Often the most overlooked setting. Downhill loads your quads differently and is genuinely useful if you are training for a race with descents. The reason a high ceiling matters is not that you will live at the top of it. It is that you never hit the wall. A treadmill that maxes at 15% eventually stops being able to challenge you, and a machine that cannot challenge you is a machine you stop using. That is the motivation cliff, and it is how good equipment quietly turns into an expensive clothes rack by month two. Aviron's answer is to make the workout itself the reason you come back. Every mode — from science-backed games to coached classes to scenic routes — is built on the same reward loops that keep you pulling at your phone. **92% of Aviron members are still working out a year later.** --- ## Which Aviron Treadmill Goes to 42%? Only the Summit. It is the incline specialist in a lineup of three, and the range is the whole reason it exists. | Model | Incline Range | Best For | |-------|--------------|----------| | Justice | 0% to 15% | Small spaces, folds upright | | Podium | 0% to 18% | Runners who still need it to fold | | Summit | -6% to 42% | Climbers and hikers | For the full breakdown, see: [Justice, Podium or Summit: Which Aviron Treadmill Is Right for You?] : https://www.avironactive.com/blog/which-aviron-treadmill-justice-podium-summit/ --- **Aviron Podium Treadmill** — If 42% is more than you need ![Aviron Podium folding treadmill](https://cdn.builder.io/api/v1/image/assets%2F45e65c713405486e8fe2ec324b61c21f%2F6484e4779e37405ca0ba6c6bd59c45be?format=webp&width=240&height=240&fit=cover) 18% incline, 14 mph, a 22 inch by 60 inch deck, and it still folds away when you are done. 30-day risk-free trial. Financing available. [Aviron Podium Treadmill] : https://www.avironactive.com/shop/aviron-podium-treadmill/ --- ## Frequently Asked Questions ### How many degrees is a 42% incline? A 42% grade equals 22.8 degrees. Grade and degrees are different scales: a 100% grade is 45 degrees, not vertical. To convert any grade to degrees, take the arctangent of the grade divided by 100. ### Is a 42% treadmill incline safe? Yes, for walking, at a controlled speed, holding the handles. It is not safe for running, which is why the Summit caps its top speed above 15% incline. Build up to steep grades over several weeks rather than starting there, and step off the belt to change settings if you feel unsteady. ### Does incline walking burn more calories than running? It can. Steep incline walking pushes your heart rate into the same zones as running while keeping both feet in regular contact with the belt, so impact on your joints stays much lower. For many people that trade means longer, more frequent sessions, which matters more over a year than any single workout. ### What is a good incline for beginners? Start between 1% and 3% for regular walking, then work toward 10% to 12% as your fitness improves. The 12-3-30 workout — which uses a 12% incline at 3 mph for 30 minutes — is a reasonable target for most people within a few months. ### Why does a treadmill need a decline setting? Downhill walking loads your quadriceps eccentrically, which is a different demand from anything you get going uphill or on the flat. If you hike, trail run, or race anything with descents, training the downhill is how you avoid the sore legs that show up two days after the event. The Summit goes to a 6% decline. --- ## Climb Something Worth Climbing The Summit goes from a 6% decline to a 42% climb, and every workout on it is built to make you want the next one. 30-day risk-free home trial. Free shipping. 0% APR financing available. [Aviron Summit Treadmill] : https://www.avironactive.com/shop/aviron-summit-treadmill/ --- **Related reading:** - [12-3-30 Treadmill Workout] : https://www.avironactive.com/blog/12-3-30-treadmill-workout/ - [Justice, Podium or Summit: Which Aviron Treadmill Is Right for You?] : https://www.avironactive.com/blog/which-aviron-treadmill-justice-podium-summit/ **Canonical URL:** https://www.avironactive.com/blog/how-steep-is-42-percent-treadmill-incline/