Solar Panel Tilt Angle Calculator
Find the angle that gets the most sun onto your panels. Enter a latitude (or choose a city) to get the best year-round fixed tilt, the angles for adjusting four times a year, a month-by-month table, the compass direction to face and the matching roof pitch.
Last updated:
Positive = north, negative = south (e.g. -33.87 for Sydney).
Compare your roof angle with the optimum, e.g. 6 for a 6/12 roof.
How to use the Solar Panel Tilt Angle Calculator
- Choose your city or select 'Enter latitude' and type your latitude (negative for the southern hemisphere).
- Read the best fixed tilt if your panels will never be adjusted.
- Use the seasonal angles if your racking can be adjusted two or four times a year.
- Check the monthly table for adjustable or tracking mounts, and the chart to see how the angle swings through the year.
- Point the panels toward the azimuth shown (true south in the northern hemisphere, true north in the southern).
How the tilt angles are calculated
The sun is highest in the sky at solar noon, and its height changes with the season because of the sun's declination (δ), which swings between +23.44° in late June and −23.44° in late December. A panel collects the most light when it faces the sun squarely, so the ideal tilt at noon is:
Tilt = latitude − declination
Over a full year, a fixed panel does best a little flatter than the latitude because long summer days carry more energy. The fixed and seasonal rules used here are latitude-based fits from solar-energy researcher Charles Landau:
| Setting | Formula (latitude φ in degrees) | At 40° |
|---|---|---|
| Fixed, year-round (φ 25°–50°) | φ × 0.76 + 3.1° | 33.5° |
| Fixed, year-round (φ under 25°) | φ × 0.87 | — |
| Winter | φ × 0.875 + 19.2° | 54.2° |
| Spring & autumn | φ − 2.5° | 37.5° |
| Summer | φ × 0.93 − 21° | 16.2° |
Best fixed tilt by latitude
| Latitude | Example places | Fixed tilt | Winter | Summer |
|---|---|---|---|---|
| 20° | Honolulu, Mumbai, Mexico City | 17.4° | 36.7° | 0° |
| 25° | Miami, Dubai | 22.1° | 41.1° | 2.3° |
| 30° | Houston, Cairo, Perth (S) | 25.9° | 45.5° | 6.9° |
| 35° | Los Angeles, Tokyo, Sydney (S) | 29.7° | 49.8° | 11.6° |
| 40° | New York, Madrid, Beijing | 33.5° | 54.2° | 16.2° |
| 45° | Minneapolis, Milan | 37.3° | 58.6° | 20.9° |
| 50° | Vancouver, Frankfurt, Kraków | 41.1° | 63.0° | 25.5° |
Direction (azimuth)
Face panels toward the equator: true south (180°) in the northern hemisphere and true north (0°) in the southern hemisphere. Magnetic compasses can be off by more than 10° in some regions, so apply your local magnetic declination. If time-of-use electricity rates make evening power more valuable, turning panels somewhat west can be worth a small loss in total yield.
Frequently asked questions
What is the best tilt angle for solar panels?
For a fixed system the best year-round tilt is close to your latitude, slightly flatter in practice. A widely used rule for latitudes between 25° and 50° is tilt = latitude × 0.76 + 3.1°. At 40° N that gives about 33.5°. Below 25° multiply the latitude by 0.87.
Which direction should solar panels face?
In the northern hemisphere panels should face true (geographic) south, an azimuth of 180°. In the southern hemisphere they should face true north (0°). A compass shows magnetic north, which can be several degrees off, so correct for your local magnetic declination. Facing up to about 20° to 30° east or west of the ideal usually loses only a few percent of yearly output.
How do I calculate the solar panel angle for each month?
Subtract the sun's declination for that month from your latitude: tilt = latitude − declination. The declination ranges from +23.44° at the June solstice to −23.44° at the December solstice, so panels should be steeper in winter and flatter in summer. The monthly table on this page uses the mid-month declination.
Is it worth adjusting solar panels seasonally?
Adjusting four times a year typically gains only a few percent over a well-chosen fixed tilt, and twice a year gets most of that gain. It is most worthwhile on ground mounts and off-grid systems that need extra winter output; roof-mounted grid-tied systems are almost always left fixed.
What tilt should I use in winter for an off-grid system?
Off-grid systems usually size for the darkest month, so a steeper winter angle helps. A common rule is latitude × 0.875 + 19.2°, which is around 54° at 40° latitude. Steeper panels also shed snow better.
What if my roof pitch is different from the ideal angle?
Small differences matter little: a tilt within about 10° to 15° of the optimum usually loses only a few percent of annual energy. That is why most rooftop systems simply follow the roof. On a flat roof, tilt racks of 10° to 30° are common, limited by wind loads and row shading.
Is my location sent anywhere?
No. You choose or type a latitude and everything is calculated in your browser. The page does not request your GPS position.
Are all the tools on FreeToolCabin tested for quality and accuracy?
Yes! Every tool on our site undergoes automated Q/A testing in real browser environments to ensure high precision, correct output, and zero errors. If you happen to spot a bug or have a suggestion, please contact us at [email protected] and our team will review it right away.