Solar Panel Angle Calculator
Find the optimal tilt angle for your solar panels based on latitude and season.
Working with solar electrical output? Try our Watts/Amps/Volts converter.
Input
Result
Monthly Tilt Angles
Formulas
Year-round: Tilt ≈ Latitude
Summer: Tilt = Latitude − 15°
Winter: Tilt = Latitude + 15°
Monthly: Tilt = Latitude × 0.9 − Seasonal Offset
Understanding Solar Panel Angles
The angle at which solar panels are tilted significantly affects their energy production. The optimal tilt angle depends on your latitude — locations closer to the equator need a flatter panel, while higher latitudes require steeper tilts. By adjusting your solar panels to match the sun's position throughout the year, you can maximize energy harvest and improve the return on your solar investment. This calculator provides year-round, seasonal, and month-by-month recommendations so you can choose the best setup whether you have fixed or adjustable mounts.
Formulas
The year-round angle is a simple rule of thumb that works well for fixed installations. Seasonal adjustments (adding or subtracting 15°) account for the sun's higher path in summer and lower path in winter. The monthly formula with seasonal offsets provides finer-grained tuning for adjustable tilt mounts.
How to Use This Calculator
Frequently Asked Questions
What is the best angle for solar panels?
The best year-round angle for solar panels is approximately equal to your latitude. For example, at 35° latitude, tilt your panels at about 35° from horizontal. For better seasonal performance, subtract 15° in summer (when the sun is higher) and add 15° in winter (when the sun is lower). This gives you the best average energy production over the entire year.
Do solar panels need to face south?
In the Northern Hemisphere, solar panels produce the most energy when facing south (true south, not magnetic south). In the Southern Hemisphere, they should face north. This orientation maximizes exposure to the sun's path across the sky. However, east- or west-facing panels can still produce 70–85% of optimal output, which may be preferable depending on your roof orientation or time-of-use energy rates.
How much does tilt angle affect solar output?
Tilt angle can affect solar output by 10–40% depending on your latitude and the season. At higher latitudes, the impact is greater because the sun's angle varies more throughout the year. A panel tilted 20° off the optimal angle may lose 5–10% of its potential output. Being 40° off optimal can reduce output by 20% or more, especially in winter when the sun is low.
Should I adjust my solar panels seasonally?
If you have adjustable mounts, seasonal adjustment can boost annual energy production by 5–15%. The simplest approach is to change the tilt twice a year: set it to latitude minus 15° for summer and latitude plus 15° for winter. Monthly adjustments offer marginal additional gains. For fixed roof-mounted systems, the year-round optimal angle (≈ latitude) is usually the best practical choice.
What if my roof pitch doesn't match the optimal angle?
Most roof-mounted systems are installed at the roof's pitch, even if it's not perfectly optimal. A roof pitch within 10–15° of the optimal angle typically loses less than 5% output. If the mismatch is larger, consider using tilt-up mounting brackets that add an angle offset to the roof pitch. For flat roofs, mounting systems allow you to set any angle, usually around 20–30° for good drainage and wind resistance.