Solar panel tilt angle calculator

The Solar panel tilt angle calculator computes solar panel tilt angle from the relation tilt approx latitude. It takes a single input (latitude in deg) and returns the optimal tilt in deg. Because this is a pure mathematical or physical formula rather than a jurisdiction-specific rule, the result never changes over time: the same inputs always produce the same answer, so you can rely on it whether you are checking homework, sizing a design, or sanity-checking another tool. Enter your values in the fields below and the result updates instantly; you can also share a permalink that pre-fills the exact calculation, which is useful for teaching, reports, or collaboration. For example, with latitude = -35 deg, the optimal tilt works out to 35 deg, and the worked example further down the page shows every step so you can follow the arithmetic and reproduce it by hand. The method is the standard form documented by Documented methodology, and the figure above each result carries the date it was last verified. This tool is general information and is not a substitute for professional engineering, medical, financial, or scientific advice; always check critical results against the primary source and your own judgement.

With Latitude = -35 deg, the result is 35 deg.

Formula: tilt approx latitude. Source: Documented methodology, as at 2026-06-23.

Optimal tilt35 deg

Applies to: any numeric inputs. Method source: Documented methodology, checked 2026-06-23.

The formula

tilt approx latitude

Worked example

With Latitude = -35 deg:

  1. optimal fixed tilt approx latitude
  2. Optimal tilt = 35 deg

This worked example is one of the automated golden-value tests this calculator must pass before it can publish.

What this assumes

  • Inputs are real numbers in the units shown.
  • The result is the exact value of tilt approx latitude; general information, not professional advice.

Frequently asked questions

What formula does this use?

tilt approx latitude, the standard form documented by Documented methodology.

Does the result ever change over time?

No. This is a pure formula with no external rate, so the same inputs always give the same result.

Official sources and verification

Reviewed by the CalculatorHub team, edited by James Graham, 2026-06-23. See our methodology. General information, not professional advice.