PCB Impedance Calculator — Microstrip, Stripline, Differential, CPW
This online impedance calculator solves PCB trace impedance for the structures engineers ask about most: single-ended microstrip and stripline, differential pair (edge-coupled and broadside-coupled), coplanar waveguide with and without ground, rectangular waveguide, and coaxial line. Each mode uses the same field equations the factory's impedance-toleranced v1.1 stackup checks against, so the calculator output aligns with the ±5% impedance tolerance we manufacture to on standard builds and ±3% on controlled production lots.
How to use this impedance calculator online: pick the topology, enter substrate height (H), dielectric constant (Dk), copper thickness (T), and either trace width (W) or target impedance. The solver returns matched impedance, effective Dk, propagation delay, and—where applicable—differential impedance and coupling factor. Calculations run entirely in your browser; no trace geometry leaves the page.
When to switch from this impedance calculator to a controlled-impedance PCB quote
If your design needs impedance control beyond ±10%, multilayer stackup with buried reference planes, or impedance verification via TDR coupons and cross-section microsection, request a controlled-impedance PCB quote. The calculator helps you converge on stackup; the quote locks the manufacturing tolerance, copper profile, and TDR verification plan.