How to Use PCB Trace Calculator for Printed Circuit Boards


When you’re designing a printed circuit board (PCB), you have to keep in mind all the different things that are going to be on your board. There are going to be components, and they will need to be connected to each other. The PCB trace calculator comes in helpful here.

Description of PCB Trace Calculator

A tool that can help you calculate the number of traces in your circuit board. This calculator is designed for professionals who are working with PCBs and need to know how many traces they can fit on their board.

The calculator provides you with an estimate for the number of traces you can fit on a certain area, such as a square or circle shape. It also gives you options for what kind of materials you want to use for your PCBs. For example, you can select if you want to use single-sided or double-sided copper-clad sheets for your board.

The calculator will then give you an estimate based on these selections and show it graphically so that it’s easy to understand what kind of trace density options are available.

PCB Trace Calculator

PCB Trace Calculator

How Much Current Can a PCB Trace Carry?

When it comes to PCB trace current-carrying capability, the IPC standards say that the dc current-carrying capability of a PCB trace is up to about 30 A.

This means that you can have a PCB trace that’s rated for carrying up to 30 A and you can use it in a circuit where you need more current than that. However, if you do use the trace for more current than it’s rated for, you may end up damaging your circuit or even causing a fire.

But remember, current carrying capacity of a PCB trace depends on its length and width, as well as the material from which it’s made.

PCB Trace Current

PCB Trace Current

Limit of Current Amount That Can be Calculated

The maximum trace width that can be calculated by this tool is 400 mils. The maximum current density is 35 amps per square inch and the maximum copper thickness is 3 ounces per square foot. Temperatures might rise from 10 to 100 degrees Celsius. If you enter numbers that are outside of these ranges, the calculator will extrapolate the data to provide a more accurate answer.

PCB Current Amount

PCB Trace Width

How to Use the PCB Trace Calculator?

This is a tool that can assist you in determining the ideal spacing for your printed circuit board traces. It does this by calculating the capacitance, inductance, resistance, and impedance of a trace.

The first step in using the PCB Trace Calculator is to enter all relevant data about your layout.

Normal Mode

These are the data needed to calculate PCB traces in normal mode. You have to gather the following data:


This is the first thing you need to know when using the PCB Trace Calculator. This data helps you determine how long one side of your board will be, and how much space you have to work with.

Trace Width

You can get this information from your schematic or design file. If you don’t have a schematic or design file, then you can use your own measurements for the trace diameter and length by using a caliper to measure them directly on your printed circuit board (PCB).

Trace Thickness

This is the amount of space between each trace on the circuit board. This value determines how much current can pass through a circuit without overheating or burning out. The thicker the trace, the more current it can carry, but at the same time, it also increases resistance. When designing your PCB, it is critical to examine both elements and decide if your design requires thick or thin traces.

Maximum Temperature Rise

A computation that considers the materials in the PCB trace, as well as their resistivity, thickness, and length. It’s one of the most important calculations when you’re designing a PCB trace because it helps you determine whether or not your design will be able to handle the heat produced by the current flowing through it.

Normal Mode PCB Trace Calculator

Normal Mode PCB Trace Calculator

Advanced Mode

Here’s the data you have to gather in advance mode:

Ambient Temperature

The temperature of the environment in which the PCB is being used. This value is important because it affects the thermal resistance of the traces on the PCB, and therefore determines how much heat can be dissipated from each trace. When current is delivered, the ambient temperature influences how long it takes for a trace to heat up to a given temperature.


The length of the trace must be supplied as input into the calculator. This is the distance between the beginning and end points of the trace.

Maximum Current

The maximum current is the maximum current that may be safely passed through a trace on a printed circuit board. It is measured in amps, and it’s usually listed on the datasheet for the particular component you’re using.

For example, if you’re working with a 5V power supply, then your maximum current will be 20mA (or 0.02A). This number is usually found in the datasheet for your component.

Trace Temperature

The average temperature of the PCB trace. It can be calculated by measuring the temperature of the PCB trace with a thermocouple, which is inserted into the PCB at a point halfway between the beginning and end of each trace.


The amount of electrical current that travels through a printed circuit board trace is measured in ohms. This value can be calculated by dividing the voltage across the trace by its current.

Voltage Drop

It’s calculated by dividing the total resistance of the trace by its length and is usually expressed as millivolts per inch (mV/in). Voltage drop in a circuit can be caused by any number of factors: resistive materials in the PCB itself, inductive loads, and other factors.

To calculate voltage drop, you must first determine the overall resistance of your trace, which includes resistors and other resistance-based components, as well as its length.

Power Dissipation

A measure of the amount of heat generated by an electronic component or circuit. The power dissipated in a resistor, for example, is equal to the product of the current flowing through it and the voltage across it.

To determine the power dissipation of a printed circuit board trace, you must first calculate the product of the trace width and height. You can then divide this number by the thermal resistance of your material to get your final answer.

Advance Mode PCB Trace Calculator

Advance Mode PCB Trace Calculator

Formula of PCB Trace Calculator IPC-2221 Standard

After you have gathered all of the necessary data to compute the printed circuit board trace, you may utilize a PCB Trace Calculator that follows the IPC-2221 Standard formula. This formula is the following:

Area[mils^2] = (Current [Amps] / (k*(Temp_Rise [deg. C]) ^b)) ^(1/c)

Width is calculation:

Width[mils] = Area[mils^2]/(Thickness[oz]*1.378[mils/oz])

Internal Layer Calculation

Based on IPC-2221 Standard, the values needed to input in the mentioned formula if you are calculating internal layers should be the following:

k = 0.024, b = 0.44, c = 0.725

External Layer Calculation

IPC-2221 specifies the following values for external layers when calculating them:

k = 0.048, b = 0.44, c = 0.725

PCB Trace Calculator IPC-2221 Standard

PCB Trace Calculator IPC-2221 Standard

Formula for Resistance Calculation

When going through the trace resistance calculation, start by changing the cross-section area from [mils2] to [cm2].

You can do this by multiplying the mils by 2.54, then multiplying that result by 2.54 again, and then dividing the result by 10-6.

After completing this calculation, you’ll quantify your trace resistance using:

R = (ρ * L / A’) * (1 + α * (TTEMP – 25 °C)).

Resistance Calculation

Resistance Calculation

Formula for Voltage Drop Calculation

Voltage drop is the decrease of electrical potential as it moves through a current in an electrical circuit. The equation for determining voltage drop is:

VDROP = Maximum Current * Trace Resistance.

Maximum current is the current that will cause the most significant voltage drop in your circuit, and trace resistance is the resistance of the conductor used to route that maximum current.

Voltage Drop Calculation

Voltage Drop Calculation

Formula for Power Dissipation Calculation

Power dissipation is the amount of electrical energy that is converted into heat. It happens when an electrical gadget creates heat, which causes energy loss or waste. The standard IPC-2221 defines power dissipation as:

PLOSS = Resistance * Maximum Current²

Power Dissipation Calculation

Power Dissipation Calculation

Reasons to Use a Trace Width Calculator

If you’re in the process of designing a circuit, then it’s likely that you’ve already started to figure out the different elements that need to be included. You’ve probably considered resistors, capacitors, and inductors. You’ve probably even thought about how much space each element will take up on your board.

A trace width calculator is a handy tool that can help you determine the proper width of a trace in your PCB design. This can be used to ensure your circuit works properly, and it can also help you reduce the amount of waste you create when you’re making a PCB.

The main reason why you should use a trace width calculator is that if you don’t, you might end up with an incomplete circuit or even a non-functional one. This can be frustrating for both hobbyists and professionals alike who want to make sure their circuits work correctly before they send them to production.

What Unit of Measure is Mils?

Mils is a unit of measurement that is used in printed circuit board manufacturing. It is a unit of measurement that describes the thickness of a soldermask. For example, if you have a soldermask that is 1 mil thick, it means that it is 1 thousandth of an inch thick.

It’s usually used by manufacturers to describe the thickness of layers on the board, and it’s also used to describe how thick the solder is that will be used to connect components to the copper traces.

What Does Temperature Rise Mean?

Temperature rise is the difference between the temperature of a solder joint when it is first exposed to heat, and its temperature when it has cooled down.

This increase in temperature can be measured and controlled in the printed circuit board manufacturing process, as it is necessary to ensure that the solder that connects components to the printed circuit board doesn’t melt before it should.

It’s important to know how much temperature will rise in a printed circuit board manufacturing process because it can help you determine whether or not a component will crack due to thermal expansion.



There is a lot to consider when designing a circuit board, and your first goal should be to make sure that it can be done safely and efficiently. By taking the time to build a solid foundation with a circuit diagram, you can ensure that your PCB will function as intended once it has been properly manufactured. This will save you time and money in the long run and will allow you to focus on the fun stuff: actually getting the circuit board made.

PCB Trace Calculator can handle numerous PCB needs for any given circuit and is highly user-friendly. Simply type in the data that is asked for, and you can instantly determine what trace width will be needed for every single layer of the board. By using this, you’re making sure that there is no wasted space and you can be sure your design is flawlessly executed.

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