A hammock ridgeline calculator finds the correct strap and ridgeline lengths for any tree spacing and hang angle. The standard 30-degree hang angle provides the ideal balance between comfort, tension, and structural sag. Getting the angle right prevents both over-taut hammocks (uncomfortable) and sag that puts you too close to the ground.
Hammock Setup Details
30° is recommended — ideal comfort and structural balance
How to Calculate Hammock Ridgeline and Strap Length
Getting your hammock hang angle right is critical for comfort and safety. Too flat and you can't sleep diagonally — too steep and the hammock fabric wraps tight and you feel like a taco. This calculator solves the geometry for any tree spacing and desired angle.
Step 1: Measure Tree Distance
Pace out the distance between your two anchor trees. For best results, choose trees 12–18 feet (3.7–5.5m) apart and at least 8 inches diameter at attachment height. Switch between feet and meters using the unit toggle. Distance is measured trunk-to-trunk, not outer bark.
Step 2: Set Your Hang Angle
The 30° angle is the hammock community standard for good reason — it provides a comfortable diagonal lay while keeping tension manageable. Angles below 25° create very high tension that stresses hammock fabric and tree anchor points. Angles above 40° make the diagonal sleeping position uncomfortable because the head and foot ends sit too high.
Step 3: Enter Hammock Length
The hammock length helps calculate the ridgeline. A structural ridgeline (cord attached between the two suspension points) is typically set at 83% of hammock length — this determines sag regardless of tree distance. The ridgeline length from the calculator represents the total cord length from attachment point to attachment point along the suspension.
Step 4: Read the Results
The calculator gives you: ridgeline length (total cord tree-to-tree), total suspension length (including hammock), strap length per side, and how far your attachment points drop below the baseline. Use these measurements to pre-cut your whoopie slings or webbing straps to the right length before your trip.
FAQ
Is this hammock ridgeline calculator free?
Yes, completely free with no signup required. Enter your tree distance and target angle to get strap length instantly.
Is my data safe and private?
Yes. All calculations run locally in your browser. No data is sent to any server or stored.
What is the ideal hammock hang angle?
30 degrees below horizontal is the widely recommended hang angle for most hammocks. At 30°, you get a comfortable slightly-asymmetric diagonal lay, balanced tension on the fabric, and reasonable strap length. Angles flatter than 25° create too much tension. Steeper than 35° makes diagonal sleeping uncomfortable.
What is a ridgeline on a hammock?
A ridgeline is a fixed-length cord stretched between the two anchor points (trees) at the top of the hammock. A structural ridgeline (typically set at 83% of the hammock length) determines the sag of the hammock regardless of tree spacing. A non-structural ridgeline sits above the hammock for gear storage or a tarp.
How long should my hammock straps be?
Strap length depends on tree distance and target hang angle. The calculator gives you the total suspension length needed from tree to tree. Typical hammock straps are 6–10 feet long. Leave enough length for wrapping around the tree (2–3 wraps) and adjusting height. The calculator includes these adjustments.
How far apart do trees need to be for a hammock?
Most hammocks work best with trees 12–18 feet (3.7–5.5m) apart. Under 10 feet creates very steep hang angles that strain the fabric. Over 20 feet requires very long straps to maintain a 30° angle. If trees are far apart, you may need to hang lower or use a longer hammock.