Free PCB stackup calculator
PCB Stackup Calculator: Layer Order, Dielectric & 50 Ω Width
Estimate a symmetric stack-up from layer count, finished thickness and copper weights, with suggested signal/plane order and an approximate 50 Ω trace width.
Calculator
Stackup calculator.
Average dielectric per gap
- Total dielectric
- —
- ≈50 Ω outer microstrip width
- —
| Layer | Role | Copper / thickness |
|---|
Planning estimate with evenly split dielectric and an IPC-2141 width estimate. Real stack-ups use available core/prepreg thicknesses; we return a buildable stack-up with your quote.
Stackup design principles
Stackup design principles.
A good stack-up gives every high-speed signal layer an adjacent solid reference plane, places power and ground planes close together for interplane capacitance, and is symmetric about the center so the board stays flat through lamination and reflow. It also uses the fewest layers that route the board, because each layer pair adds cost.
Common stackup configurations
Common stackup configurations.
| Layers | Typical order | Notes |
|---|---|---|
| 4 | SIG / GND / PWR / SIG | Lowest-cost with planes |
| 6 | SIG / GND / SIG / PWR / GND / SIG | Inner stripline layer |
| 8 | SIG / GND / SIG / PWR / GND / SIG / GND / SIG | Every signal next to a plane |
| 10+ | Alternating signal/plane pairs | DDR, PCIe, multi-rail |
Material selection by layer
Material selection by layer.
Most stack-ups use one laminate throughout, but hybrids put low-loss materials only where they are needed: Megtron on SerDes layers, Rogers on RF layers, and high-Tg FR-4 for power and control. Mixing materials needs compatible Tg, CTE and resin systems, which we confirm when we return the buildable stack-up.
Thickness planning
Planning finished thickness.
Finished thickness is the sum of copper, cores, prepregs and solder mask, plus plating on outer layers. 1.6 mm is the default; thinner boards need thinner cores and prepregs, which raises impedance-control sensitivity, and thicker boards push drill aspect ratio. Keep finished-thickness tolerance (typically ±10%) in mind for edge connectors and card guides.
Impedance link
How the stack-up sets impedance.
Dielectric height between a trace and its reference plane is the biggest lever on impedance after trace width. Thin prepregs under outer layers make 50 Ω microstrip narrow, and thicker ones make it wide. Pick dielectric thicknesses that give practical widths for your routing density, then check them with the impedance calculator.
Example stack-ups
Example 1.6 mm stack-ups.
| Layers | Example construction (1.6 mm) | Notes |
|---|---|---|
| 4 | 1 oz / 0.2 mm PP / 1.065 mm core / 0.2 mm PP / 1 oz | Thin outer prepreg → ≈ 8–10 mil 50 Ω microstrip |
| 6 | Outer PP 0.1 mm, two 0.36 mm cores, centre PP | Inner stripline + outer microstrip |
| 8 | Outer PP 0.1 mm, three cores, two inner PPs | Every signal next to a plane |
These show how core and prepreg choices change trace widths. Thinner dielectrics under signal layers give narrower 50 Ω traces and tighter coupling to the plane.
Stack-up rules
Stack-up rules of thumb.
- Keep the stack-up symmetric about the center to prevent warp
- Put every high-speed layer next to a solid reference plane
- Pair power and ground planes closely for capacitance
- Balance copper on mirrored layers
- Use the fewest layers that route — see multilayer PCB and HDI PCB
FAQ
Tool questions.
What is a PCB stackup?
The order, material and thickness of copper and dielectric layers in a multilayer board.
Is the result a buildable stack-up?
It is a planning estimate. Your quote includes a buildable stack-up using real core and prepreg thicknesses.
How thick is a standard PCB?
1.6 mm (0.062 in) is the most common finished thickness.
How many layers do I need?
Enough signal layers to route the densest area plus the planes they need for impedance and power, kept symmetric. Four is the minimum for solid planes.
Should power and ground be adjacent?
Yes where possible; close spacing adds interplane capacitance and lowers PDN impedance.
Can I mix materials in one stack-up?
Yes, in hybrids, provided Tg, CTE and resin systems are compatible.
Ready when your files are
Done designing? Get it built.
Upload Gerber, ODB++ or IPC-2581 data. Every quote includes a written engineering DFM review, typically within one business day.