SPRNGLY.NET

The Fastest Way to Select a Spring for Any Application

Why traditional spring calculations and distributor search filters waste hours of engineering time—and how Springly solves it with inverse kinematic matching.

The Problem with Conventional Spring Sizing

Every mechanical engineer has experienced the frustration of manual spring lookup.

1

The Textbook Formula Trap

Standard textbook equations (like k = G·d&sup4; / (8·D³·N)) are forward-solving equations. They require you to already know the wire diameter d, mean diameter D, and active coil count N.

In real design work, you don't know the geometry yet—you only know your stroke length, preload force, and maximum working force!

2

Clunky Distributor Filters

Distributor websites force you to filter through drop-down menus: Free Length, Wire Diameter, Outside Diameter, and Spring Rate.

If you filter for a 2.00" free length, you completely miss a 2.25" catalog spring that fits your housing perfectly when pre-compressed to your installed length.

How Springly Solves It: The Inverse Search Engine

Instead of guessing dimensions, you provide the only numbers you actually know:

Step 1: Preload

Installed Length & Force

Length at rest & initial retaining force.

Step 2: Working

Operating Length & Force

Length at full stroke & required return force.

Step 3: Envelope

Hole / Rod Constraints

Optional Max OD (hole) or Min ID (rod).

Springly immediately calculates the required spring rate (k = ΔF / ΔL), mathematically scans thousands of verified Century Spring Corp off-the-shelf catalog springs, checks solid height safety clearances, and ranks the best matches by minimal force error.

4-Step Workflow

  1. 1
    Enter Assembly Dimensions: Specify your installed height, working height, and forces in either Imperial (in / lbf) or Metric (mm / N).
  2. 2
    Run Calculation & Compare: Springly produces a clean side-by-side comparison table showing actual forces, travel, solid length clearance, and total error percentage.
  3. 3
    Inspect 3D Geometry: Click any part number to open its 3D preview, complete with realistic wire pitch and flat closed & ground end cuts.
  4. 4
    Download CAD Directly: Grab standard solid CAD files (.STEP) or 3D meshes (.STL) for instant import into SolidWorks, Inventor, Fusion 360, or Onshape.

Ready to size your spring?

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Open Springly Selector →