Calculate swing radius, the horizontal reach of a swing, rope or chain, from its length and angle from vertical, or solve for the length or angle.

Ideal geometry, angle 0ยฐโ€“90ยฐ from vertical. Not a playground use-zone or crane-capacity check.

Optional settings
Extra clearance added to the radius; blank means zero. Your own allowance, not a safety standard.

Related Calculators

Swing Radius Formula

The following formula is used to calculate the swing radius.

R = L ร— sin(ฮธ)

Variables:

  • R is the swing radius (meters)
  • L is the length of the rope or chain (meters)
  • ฮธ is the angle from vertical (degrees)

Multiply rope or chain length by sin(ฮธ), with ฮธ measured 0ยฐโ€“90ยฐ from vertical. Select radius, length or angle explicitly. Circle-area and circumference inverses find the unbuffered radius before adding the optional buffer; blank buffer means zero.

What is a Swing Radius?

Here swing radius is the horizontal displacement of an ideal point at the end of a straight rope or chain from the vertical line through its pivot. The buffered circle is only a layout model. Actual playground use zones require swing-specific guidance, including pivot height and protective surfacing; crane operation requires manufacturer data. A geometric fit is not a safety approval.

How to Calculate Swing Radius?

The following steps outline how to calculate the Swing Radius.

  1. First, determine the length of the rope or chain (L) in meters.
  2. Next, determine the angle from vertical (ฮธ) in degrees.
  3. Convert the angle from degrees to radians by multiplying it by ฯ€/180.
  4. Use the formula R = L * sin(ฮธ) to calculate the Swing Radius (R) in meters.
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

Length of Rope/Chain (L) = 5 meters

Angle from Vertical (ฮธ) = 30 degrees. R = 5 ร— sin(30ยฐ) = 2.5 meters, before any buffer.