Solar Panel Tilt Angle Calculator

This solar panel tilt angle calculator gives the best angle for solar panels in your city: one fixed angle for the whole year, plus summer and winter angles if your stand can be adjusted. Pick your city above and it shows the result instantly. Below we explain how the angle is worked out from latitude, which direction panels should face in Pakistan, and how to check the angle on your own roof.

How the calculation works

The sun is lower in the sky in winter and higher in summer, and it is always to the south of us in Pakistan. A panel collects the most energy when it faces the sun squarely, so the tilt depends on how far north of the equator you are, which is your latitude.

The calculator uses three simple rules:

1. Year-round angle = your latitude. Lahore is at about 31.5° north, so a fixed panel works best at about 32° from flat.
2. Summer angle (April to September) = latitude minus 15°. The sun is high, so the panel lies flatter.
3. Winter angle (October to March) = latitude plus 15°. The sun is low, so the panel stands steeper.

And one rule for direction: face the panels due south. Not towards the street, not towards the gate, but true south.

Setting	Formula	Lahore example
Fixed, all year	Latitude	32°
Summer (Apr to Sep)	Latitude − 15°	17°
Winter (Oct to Mar)	Latitude + 15°	47°
Direction	Due south	South (180° on a compass)

What “tilt angle” means

Tilt is measured from flat. A panel lying on the roof is at 0°, a panel standing straight up like a wall is at 90°. When an installer says “32 degrees”, the front edge of the panel is low and the back edge is raised so the face points up and towards the southern sky. The other angle you will hear about is azimuth, the compass direction the panel faces. In Pakistan the target azimuth is south, written as 180°.

Why latitude, and how precise it needs to be

The latitude rule is the standard starting point used by installers around the world for a fixed system. Many simulation tools put the very best fixed angle a few degrees below latitude in places with hazy or cloudy summers, because more of the year’s energy then comes from a high summer sun. In practice the difference is small: anywhere within about 5° of the calculator’s figure loses only a percent or two over a year. So do not worry if your stand comes in at 28° or 30° instead of 32°. Worry if it is flat, or facing east.

Worked examples: Lahore, Karachi and Islamabad

Three cities show how much latitude changes the solar panel angle across Pakistan.

City	Latitude	Fixed angle	Summer	Winter	What it means on the roof
Karachi	24.9° N	25°	10°	40°	Fairly flat panels; low wind load
Lahore	31.5° N	32°	17°	47°	Check a ready-made stand’s angle before buying
Islamabad	33.7° N	34°	19°	49°	Steeper; needs firm anchoring for wind

Karachi

At 25°, Karachi’s panels sit flatter than anywhere else in the main cities. That helps in two ways: the structure catches less of the strong sea breeze, and rows can sit closer together because they cast shorter shadows. The trade-off is dust and salt settling more easily on a flatter panel, so wash more often.

Lahore

Lahore’s fixed angle is about 32°. If you are buying a ready-made stand, ask for the tilt in degrees, because ready-made frames are not all built to the same angle. During the December and January fog, output falls whatever the angle, so a steeper winter setting helps only on clear days.

Islamabad

Islamabad and Rawalpindi at about 34° need the steepest fixed angle among the big cities, along with Peshawar. A steeper panel stands taller and catches more wind, so the structure needs firm anchoring, especially on open, exposed top floors. Because the winter sun is lowest here, rows also need the widest gaps.

Tilt on different roof types

The best angle for solar panels is the same whatever the roof, but how you reach it changes:

• Flat RCC roof (most Pakistani houses). A steel stand sets the angle. You have full control, so build to the calculator’s figure and face south even if the house itself is turned.
• Elevated structure. Popular where people want parking or shade under the panels. The angle is the same, but height adds wind load, so the frame and base need to be stronger.
• Sloped roofs, sheds and godowns. Panels often go flush on the existing slope. If the slope faces south and is within about 10° of your latitude, flush mounting is fine. If it faces north, use a tilted frame or another roof.
• Shop and plaza roofs with limited space. A flatter angle, around 15° to 20°, lets you fit more rows with less shading, which often wins on total units.

Solar panel tilt angle for every major city

Here are the results for all the cities in the calculator. The row gap is the minimum clear space between one row’s back edge and the next row’s front edge, so the front row does not shade the back row at noon on the shortest winter day. It assumes one large 540 to 590 W panel (about 2.28 m long) mounted portrait at the fixed angle.

City	Fixed angle	Summer	Winter	Winter noon sun height	Minimum row gap
Karachi	25°	10°	40°	about 42°	about 1.1 m
Multan	30°	15°	45°	about 36°	about 1.6 m
Faisalabad	31°	16°	46°	about 35°	about 1.7 m
Lahore	32°	17°	47°	about 35°	about 1.7 m
Gujranwala	32°	17°	47°	about 34°	about 1.8 m
Islamabad	34°	19°	49°	about 33°	about 2.0 m
Rawalpindi	34°	19°	49°	about 33°	about 2.0 m
Peshawar	34°	19°	49°	about 33°	about 2.0 m

That gap is the noon minimum. To keep the back row clear from about 9 am to 3 pm in December, leave more, roughly one and a half times the figure. If roof space is tight, a slightly flatter angle with closer rows usually produces more in total than a perfect angle with fewer panels.

Solar panel direction

Direction matters more than a few degrees of tilt. Expected output for a fixed panel at the right tilt, compared with facing due south:

Panels face	Output compared with south
South	Best
South-east or south-west	Slightly less, often a few percent
East or west	Noticeably less, often 10 to 20%
North	Poor; avoid in Pakistan

Facing a little west is not always a loss. If your house uses most power in the afternoon, for example ACs from 2 pm, a south-west facing array shifts output later in the day, which matters more under net billing, where daytime self-use is worth more than exported units.

Is seasonal adjustment worth it?

Moving panels twice a year, to the summer angle in April and the winter angle in October, adds a few percent of output over a fixed setting. On a small home system that is worth doing only if the stand is built to adjust safely. On a large or high structure, the risk of loosened bolts and someone working on the roof usually outweighs the gain. Most homes are best served by fixing the year-round angle and spending the effort on regular cleaning instead.

Tips for an accurate result

The solar panel installation angle calculator above gives the target. Getting it right on the roof takes a few simple checks.

1. Find true south. A phone compass works, but stand away from steel water tanks and the structure itself. Compass apps point to magnetic south, which in Pakistan is only a few degrees from true south, so that is close enough for solar.
2. Measure the tilt. Lay a phone with a level or angle app flat on the panel frame. Or measure the rise and the run of the stand and use the angle: a 2.28 m panel at 32° rises about 1.2 m from front to back.
3. Check shade at three times. Look at 9 am, noon and 3 pm, ideally in December when shadows are longest. Water tanks, stair rooms and parapets are the usual problems.
4. Allow for wind. Steeper panels catch more wind. Use proper anchoring and a structure designed for the angle; our solar panel stand price page covers common options.
5. Keep cleaning easy. Panels below about 10° stay dusty because rain does not wash them. Even in Karachi, many installers avoid going flatter than 10° to 15°.
6. Size first, angle second. The angle fine-tunes output; the number of panels sets it. Use the solar panel calculator to size from your bill, or the solar panel for AC calculator for AC loads.

When to choose the winter angle instead

If your system has batteries, or you mainly want to beat winter load-shedding and gas-heater bills, lean towards a steeper setting, about 5° to 10° above the year-round figure. You give up a little summer output, when there is usually surplus anyway, and gain on short winter days when every unit counts. Homes on net billing that mainly run summer ACs can do the opposite and go a few degrees flatter.

Your priority	Suggested fixed angle
Balanced, all-year output	Latitude (the calculator’s figure)
Winter output, battery backup	Latitude + 5° to 10°
Summer AC load, tight roof	Latitude − 5° to 10°

Common mistake	Effect	Fix
Panels laid flat on the roof	Dust builds up, lower winter output	Tilt at least 10° to 15°
Facing the street instead of south	Can lose a large share of output	Re-orient the structure to south
Rows too close	Back row shaded in winter	Use the row gaps above
Steep angle on a weak frame	Structure damage in storms	Match the frame to the angle

Once the angle and direction are right, the remaining choices are panels and price. Compare today’s rates on the 585 watt solar panel price page, see full budgets in solar system price in Pakistan, and check what fitters charge on the solar panel installation cost guide.