Table Leg Angle Calculator

Splayed Legs Need Trigonometry, Not Guesswork

A table or chair with splayed (angled outward) legs looks more visually dynamic and can be more structurally stable than straight vertical legs, but building it means cutting each leg at a precise angle rather than eyeballing a "lean." Given how far you want the leg's base to spread from directly under the top, and the leg's length, basic trigonometry gives the exact angle to set on a bevel gauge or tilting jig.

The Formulas

Splay Angle = atan(Offset ÷ Leg Length)
Slanted Leg Length = √(Offset² + Leg Length²)

Offset and leg length form the two legs of a right triangle, with the angle from vertical given by the arctangent of their ratio. Because a splayed leg travels diagonally rather than straight down, its actual cut length is longer than the vertical leg length alone — found using the Pythagorean theorem.

Worked Example

A leg with a 4-inch outward offset over a 28-inch vertical leg length
MetricValue
Splay angle from vertical8.13°
Actual (slanted) leg length needed28.28 in

The slanted leg length is only slightly longer than the vertical leg length at this offset — the difference grows more noticeably at wider splay angles or shorter leg lengths.

Where This Matters

  • Setting a bevel gauge or tilting jig — the splay angle is what you dial into a saw or jig before cutting the leg's top and bottom angled ends.
  • Ordering the correct blank length — because the slanted leg is longer than the straight-line vertical distance, using the vertical leg length alone to size your lumber blank leaves the leg too short once cut at an angle.
  • Matching a design reference — when replicating a splay angle from a photo or existing piece, measuring offset and height off the original and running them through this formula gives a precise angle to reproduce.

How to Use This Calculator

  1. Enter the Desired Leg Spread/Offset in inches (how far the foot sits outward from directly under the top).
  2. Enter the Leg Length in inches (the vertical height).
  3. Select Calculate to see the splay angle and the actual slanted leg length needed.

Related Calculations

Work out matching miter angles for a tabletop frame with the Miter Angle Calculator, or check joint strength for the leg-to-apron connection with the Wood Joint Strength Calculator.