About TraceWidthCalculator
Professional PCB Design Tools - Free Forever
We build free PCB design calculators that implement the IPC-2221 trace-width power law and published impedance approximations, with the assumptions shown on each page. Our mission is to make clear engineering tools accessible to everyone—from students learning PCB design to hardware engineers checking a production board.
Our Mission
TraceWidthCalculator.com was created to solve a simple problem: professional PCB design calculators were either locked behind expensive software or scattered across unreliable websites with outdated formulas.
We believe that every hardware engineer—whether working at a large company or building projects in their garage—deserves access to clear, well-documented calculation tools. That's why our core calculators are free to use, with no registration required.
Our PCB trace width calculator, via current calculator, and impedance calculator are free to use and show the formula assumptions on each page.
Why Trust Us
What the Calculators Implement
The trace-width and via-current calculators implement the IPC-2221 empirical power law. IPC-2152 is not implemented. Single-ended impedance uses published approximations (Hammerstad–Jensen-style microstrip and an IPC-2141-style stripline approximation). Each calculator lists its assumptions and limits.
Transparent Methodology
We show our formulas and explain our methodology. You can verify our calculations against your own references or PCB fabricator guidelines.
Documented Models
Trace width and via current use the IPC-2221 empirical power law; impedance uses published single-ended approximations. Results are estimates, with the assumptions shown on each page.
Corrections
When we find an error we fix it and describe material changes on the affected page. Please report anything that looks wrong through the contact page.
Formulas, input limits, disabled models, recomputable test vectors and the dated change log are on the methodology page.
Our PCB Design Tools
Trace Width Calculator
Calculate PCB trace width based on IPC-2221 standard. Determine minimum conductor width for a given current, temperature rise, and copper thickness.
Try Calculator →Via Current Calculator
Calculate via current capacity and estimate via count for high-current applications. Essential for power delivery network design.
Try Calculator →Impedance Calculator
Estimate single-ended Z0 for isolated microstrip and stripline traces. Confirm the stackup and model limits with your fabricator.
Try Calculator →Standards We Reference
IPC-2221 (Generic Standard on Printed Board Design) is the foundational standard for PCB design, replacing the older IPC-D-275. It provides the empirical formulas we use for trace width calculations, relating current capacity, conductor cross-sectional area, and temperature rise.
IPC-2152 (Standard for Determining Current Carrying Capacity in Printed Board Design) provides updated empirical data based on more recent testing. While IPC-2221 remains widely used for its conservative estimates, IPC-2152 allows for optimized designs when space is critical.
IPC-2141 (Design Guide for High-Speed Controlled Impedance Circuit Boards) provides guidelines for impedance-controlled PCB design, including formulas for microstrip and stripline configurations that we implement in our impedance calculator.
Standards Reference
- IPC-2221B - Generic PCB Design
- IPC-2152 - Current Capacity
- IPC-2141A - Controlled Impedance
- IPC-4101 - Base Materials
- IPC-6012 - Rigid PCB Qualification
Who maintains this site
This site is maintained by Jack Shi, Founder & CEO of NexaPioneer LLC (Boulder, CO, US), who is responsible for its content and for handling reports of errors. View Jack Shi on LinkedIn. This is an operating role: it is not an electromagnetic-simulation or product-safety qualification, and the calculators are design aids, not certified results.
Report a wrong number or unsupported claim through the contact page. Confirmed fixes are dated in the methodology change log.
Questions or Feedback?
We're always looking to improve our PCB design calculators. If you have questions, found a bug, or want to suggest a feature, we'd love to hear from you.