Where the sun is, for any site and hour
Latitude, day of the year and solar hour. Get the altitude and the azimuth of the sun, and the shadow a one meter pole casts.
Sun angles for shading and light
Shading devices, overhangs and the depth of a reveal are sized from where the sun is at the hours that matter: low in winter to let it in, high in summer to keep it out. Two angles describe it, the altitude above the horizon and the azimuth around the compass.
The calculator uses true solar time, where noon is the sun due south in the northern hemisphere. Clock time differs by the time zone and daylight saving; the sun does not.
For renders, the same angles set the light that makes a facade read true. Rendair apps take a time of day; use the altitude here to pick one that matches the site.
Other free tools
- Scale ConverterConvert lengths between a scaled drawing and real size at 1:50, 1:100, 1:200 and more, in metric or imperial. Free, no sign up.
- Unit ConverterConvert length, area and volume between metric and imperial units: meters, feet, square meters, square feet, cubic meters, cubic yards and more.
- Stair and Ramp CalculatorWork out risers, riser height, tread depth and total run for a stair, or the length and landings for an accessible ramp, from the total rise.
- Project Cost EstimatorEstimate a construction budget from floor area, building type and level of finish, with design fees and contingency on top. Free, for early conversations.
- Project Timeline EstimatorEstimate a building project timeline phase by phase, from brief and concept to construction and handover, by floor area and complexity.
- Material Quantity EstimatorEstimate concrete volume, brick and block counts, paint litres and tile counts from dimensions, with a waste allowance. Free, no sign up.
- Roof Pitch CalculatorWork out a roof pitch in degrees, as a ratio and as a gradient from rise and run, with the rafter length. Free, no sign up.
- Floor Area Ratio CalculatorCalculate the allowed floor area, footprint and stories from site area, floor area ratio and site coverage. Free, for early feasibility.
- Window to Wall Ratio CalculatorCalculate the window to wall ratio of a facade and check daylight with a glazing to floor area rule of thumb. Free, no sign up.
- Parking CalculatorCalculate parking spaces and parking area for housing, offices, retail and hotels at common ratios, with accessible spaces. Free, no sign up.
- Occupancy CalculatorCalculate occupant load from floor area and use, with the number of exits and total exit width it needs. Free, for a first check of a plan.
- Print Size CheckerCheck whether an image has enough pixels to print at a given size: resolution in dpi, a quality reading, and the largest print at 300 dpi.
- Aspect Ratio PlannerPlan a crop to a target aspect ratio from an image size: the exact pixel dimensions that fit and the pixels lost on each side. Free, no sign up.
- File Size EstimatorEstimate image file size from pixel dimensions and format, JPEG, WebP, PNG or TIFF, and check whether it fits an email. Free, no sign up.
The numbers are done. Now the image.
Turn the sketch, plan or model into a render the client can react to.