How Many Panels Fit On Your Roof?
Find your roof on the satellite view, click around its corners, and get the usable area, the panel count that fits, and what that would generate where you live.
Rates & prices last verified: 2026-05Search or use your location to get close, switch to Street map if you need road names to find the place, then switch back to Satellite and click every corner of your roof in order. The outline closes itself, so a rectangle takes four clicks, not three.
Setbacks, vents and wrong-facing pitches all take a bite.
| Area you traced | |
| Usable for panels | |
| Panels that fit (580 W each) | |
| System size | |
| Would generate | |
| Worth about | |
| Installed cost |
Production uses your provider's own sun hours and a 0.8 performance ratio. Value assumes 70% of it is used in the house and the rest exported. Cost is the ₱35k to ₱55k per kWp installed range (2026-05).
What this does and does not tell you
It answers the supply-side question: how much roof you have, and the biggest system that could physically fit on it. That's the upper limit, not a recommendation. Most households should size to their bill rather than to their roof, because exported power earns only the generation charge, ₱10.20 on Meralco, against the ₱15.06 you avoid paying by using it yourself.
So use this to check a roof is big enough for the system the solar panel calculator suggests from your bill. If the roof is the smaller of the two numbers, that's what really limits you, and it's worth knowing before an installer visits.
Frequently asked questions
How accurate is tracing a roof from satellite?
The area maths is accurate to well under a percent for the outline you draw, so the error is almost entirely in your tracing and in how recent the imagery is. Expect to be within a few square metres if you zoom right in and click the corners carefully. It's a figure for planning, not a replacement for someone on the roof with a tape measure.
Why only 75% usable by default?
Panels can't go right to the edge. You lose space to setbacks, to vents, pipes and antennas, to walkways for maintenance, and to whichever pitches face the wrong way. 75% is a reasonable starting haircut for a simple roof; drop it to 50% or less if yours is busy or faces several directions.
Does the direction my roof faces matter?
Yes, and this tool doesn't account for it. It assumes the panels sit at a sensible tilt facing roughly south, which is the optimum here (12° at Meralco's latitude). An east or west pitch typically gives up around 10 to 15% against that, and a north-facing pitch considerably more. Treat the production figure as the best case for the area you traced.