Hill Cheat Sheet

Reading Hill Cheat Sheets for Cycling Power and Pace — A Practical Guide

Most people encounter a Hill Cheat Sheet when they buy a bike computer or try to set up training zones, then scroll past it without really understanding what they're looking at. The Hill Cheat Sheet is essentially a lookup table that maps your functional threshold power or FTP to estimated speed, time, or power output across a range of gradients. That's it. No magic, just multiplication and division with a few correction factors layered in. The basic problem it solves is that flat-ground pacing doesn't translate to climbing. Your aerodynamic drag drops off significantly at low speeds, which means your power-to-speed ratio on a climb looks very different from your power-to-speed ratio on a flat. A Hill Cheat Sheet captures this shift so you aren't guessing whether a 5% grade at your FTP should put you at 18 km/h or 24 km/h. The table typically shows columns for gradient percentage and rows for FTP ranges (e.g., 200W, 250W, 300W, etc.), with estimated speed in km/h or mph in each cell. Some versions swap speed for time per kilometer or minute per mile, depending on what the user prefers.

How the Numbers Are Actually Calculated

Here's the part most cheat sheets skip because it requires a physics equation or two. The core formula is: P = (CdA × v² × 0.5 × × v) / + (m × g × v × sin()) / + (Crr × m × g × cos() × v) / That's a mouthful but it breaks into three components: aerodynamic drag, gravitational resistance on the incline, and rolling resistance. The cheat sheet simplifies this by assuming standard values — CdA around 0.32 for an upright road position, air density of 1.225 kg/m³, rolling resistance coefficient of roughly 0.005, and drivetrain efficiency at about 95%. When those assumptions hold, the table is fairly accurate within a few percent.

When they don't hold, you're going to have a bad day on the first big climb of the season.

Where I Got Stuck With One

Last spring I built a custom Hill Cheat Sheet for a 285W FTP using the standard assumptions, printed it out, and used it to plan a group ride that included a sustained 9% climb. My actual speed on that climb was nearly 3 km/h slower than the table predicted. The discrepancy came down to altitude — the climb was at about 1,200 meters elevation where air density drops to roughly 0.94 kg/m³, which means less aerodynamic drag. Wait, less drag should make me faster, not slower. The real issue was that my CdA had changed because I was riding a different bike with a wider tire setup (28mm instead of the 25mm I'd calibrated for), and combined with standing positions that are more common on steeper grades, the effective frontal area increased enough to offset the density benefit. I ended up adding a 7% speed reduction factor to my steep-grade columns and the table started matching reality. The most practical application is pre-ride planning. Before a route with known climbs, look up your FTP and the steepest sustained grade, then compare the predicted speed against your target finish time or pacing strategy. If the table says you'll do a 6% climb at 265W in about 14 minutes at roughly 16 km/h, and your ride plan allocates 12 minutes, you know you need to either push above FTP or accept the slower pace. Doing this calculation on the fly during a climb is impractical — the numbers change with wind, position shifts, and fatigue. That's why the Hill Cheat Sheet works best as a planning document, not a real-time navigation tool. Some cyclists laminate a small card version and keep it in their jersey pocket. Others embed the data directly into training software like TrainingPeaks or WKO5 using custom intervals that reference specific grades. Both approaches have merit depending on how much post-ride analysis you do.

What Hill Cheat Sheet Misses (And How to Compensate)

The biggest blind spot is wind. A headwind of 15 km/h at the same gradient can add the equivalent of 1–2% additional grade to your perceived effort. Crosswinds matter less for speed prediction but significantly affect stability and positioning on exposed ridgelines, which changes your CdA mid-climb. There's no clean way to factor that into a static table, so experienced riders I know just mentally add a penalty column for wind-exposed climbs. Fatigue accumulation is another factor. A Hill Cheat Sheet assumes you enter each climb fresh. On a route with multiple categorized climbs in one ride, your effective FTP drops progressively. I've seen it estimated that by the third significant climb, your climb-specific power may be 8–12% below your single-climb FTP. Accounting for this means either reducing your table values or accepting that the predictions are optimistic on multi-climb days. Weight matters more than most tables acknowledge. The gravitational component scales linearly with total mass (rider plus bike and gear). Two riders at the same FTP will have different speeds on a climb if one weighs 70 kg total and the other 85 kg, because the heavier rider has to overcome more gravity even though the power output is identical. Most Hill Cheat Sheets are built around a standard 75 kg total mass. If you're outside that range, you'll want to adjust. A simple rule of thumb: for every 5 kg above 75 kg total, subtract roughly 2–3% from predicted speed on grades steeper than 5%. Below 75 kg, add the inverse.

Building Your Own

Spreadsheet-based Hill Cheat Sheet generation is straightforward if you're comfortable with formulas. Start with your FTP, enter your total weight and estimated CdA, then iterate through gradient values from 1% to 15% in 0.5% increments. Solve for velocity given constant power. The reverse calculation — finding power needed for a target speed at a given grade — is equally simple and useful for race pacing. Free online calculators exist, but they vary wildly in the default assumptions they use. I always check whether they account for drivetrain losses and whether the rolling resistance coefficient matches your tire choice before trusting the output. A $40 tire upgrade shifting Crr from 0.005 to 0.007 barely moves the needle on a Hill Cheat Sheet, but it's the kind of detail that separates a useful reference from a rough approximation. For those who want a ready-made option, search for "Hill Cheat Sheet" along with your preferred units and FTP value. Several cycling forums host downloadable CSV or Excel files that have been validated by groups of riders. I prefer the ones that include a notes section documenting the assumptions used — transparency about the underlying physics makes it easier to adjust when conditions diverge from the baseline.

When a Hill Cheat Sheet Is the Wrong Tool

Short, punchy climbs under a minute don't benefit much from a Hill Cheat Sheet because the transient power response — the ability to deliver above FTP for brief bursts — dominates the calculation. Sprinters and track cyclists don't need these tables. Similarly, on descents, gravity becomes the primary driver and the power requirements flip entirely; a descent-specific reference would use a different formula altogether. The Hill Cheat Sheet occupies a narrow band: sustained climbs between one and ten minutes at intensities roughly between 75% and 110% of FTP. Outside that band, the predictions lose relevance. Electric assist bikes complicate the concept entirely because motor assistance changes the effective power available to overcome gravity, and the relationship between rider input and speed becomes non-linear. If you ride an e-bike, standard Hill Cheat Sheet tables will mislead you. Look for manufacturer-provided range calculators instead, or build a custom table that incorporates the motor's assistance curve.