Golden Ratio Calculator (Phi 1.618)
Enter the longer, shorter, or whole segment and instantly get all golden-ratio (phi = 1.618) values — runs 100% in your browser with no upload.
🔒 Calculated in your browser — nothing is uploaded.
What this golden ratio calculator does
The golden ratio, written with the Greek letter phi (φ ≈ 1.6180339887), appears when a length is split into two parts so that the whole is to the longer part as the longer part is to the shorter part. This calculator lets you enter just one number — the longer segment, the shorter segment, or the whole length — and instantly returns all three values. Everything recomputes live as you type, so you can experiment with sizes for typography, page layouts, logos, photography crops, product dimensions, or architectural proportions and copy any result with a single click.
How the numbers are calculated
The three parts always satisfy whole = long + short and long / short = whole / long = φ. From a known longer segment L, the shorter part is L / φ and the whole is L + L / φ. From a known shorter segment S, the longer part is S × φ. From a known whole W, the longer part is W / φ and the shorter part is W − W / φ. For example, a longer segment of 100 gives a shorter segment of about 61.803 and a whole of about 161.803, and dividing 161.803 by 100 returns φ, confirming the proportion.
Frequently asked questions
How do I use this golden ratio calculator?
Type one number, then choose whether it is the longer segment, the shorter segment, or the whole length. The other two values appear instantly and can be copied with one click.
What exact value of phi does it use?
It uses φ = 1.6180339887, an approximation of (1 + √5) / 2 accurate to ten decimal places, which is far more precise than any real-world measurement needs.
Is anything I enter uploaded to a server?
No. Every calculation runs locally in your browser with JavaScript. The number you type is never sent, stored, or logged anywhere.