Golden Spiral Calculator — Fibonacci Spiral Overlay
Calculate golden spiral overlay dimensions, focal point and phi grid lines for your image frame.
Width in pixels
Height in pixels
Corner where the spiral converges
Pre-fills image dimensions
How We Calculate This
The golden spiral is constructed from successive golden rectangles, each divided into a square and a smaller golden rectangle.
Focal Point
Default focal X = width / phi (61.8% from left)
Default focal Y = height / phi (61.8% from top)
Phi Grid
The phi grid places lines at 1/phi (38.2%) and 1 - 1/phi (61.8%) of each dimension, compared to 33.3% and 66.7% for the rule of thirds.
Frequently Asked Questions
Related Calculators
Rule of Thirds Calculator
Calculate rule of thirds grid intersection points for any image size. Get exact pixel coordinates for placing key subjects on the grid. Free online calculator.
Golden Ratio Calculator
Find golden ratio division points for compositional guides at any image resolution. Place subjects using the 1.618 proportional split. Free online photography calculator.
Panorama Calculator
Plan panorama shots with recommended overlap percentage, number of frames and total field of view coverage. Get sharp, seamless stitches. Free online calculator.
Photo Merge Calculator
Calculate the final resolution and file size when merging multiple images into a panorama or composite. Plan storage and output dimensions. Free calculator.
Symmetry Calculator
Find the precise centre lines and symmetry axes for your frame dimensions. Achieve perfect symmetrical compositions in architecture and reflections. Free calculator.
Last updated: March 2026
All calculations are estimates based on standard optical and photographic formulas. Results may vary with specific equipment.