FAQ
Frequently asked questions
The questions we get most often about using Patterndo. If you do not find what you need, let us know on the contact page.
Is Patterndo free? Do I need to sign up?
It is free, and you can use it right in your browser with no sign-up or login.
Ads (Google AdSense) may appear on reading pages such as the guides and calculators. There are no ads on the editor screen.
Is there a website or program for drawing perfboard layouts?
Patterndo is exactly that: a website for drawing perfboard layouts. Without installing anything, open /editor in your browser and place parts and draw wires and jumpers on the same 2.54 mm grid as a real perfboard.
Unlike a layout drawn on paper, in Excel, or in PowerPoint, it works out the connections (nets) from the wires you draw, so you can check for shorts and polarity mistakes and even simulate whether an LED lights up before you solder. One flip shows the copper side you will solder, mirrored exactly as it will look.
Where is my board saved?
Every time you edit, the editor compresses the current board and updates the ?b= value in the address bar. Bookmark or copy the same address and you can reopen the board exactly as it was.
There are no accounts, so no server keeps the board for you. For boards that matter, make a short link with [Share], or download a JSON file with [More → Export RAW] and keep it yourself. Clearing your browser history may also remove the board stored in the address.
What parts can I use?
You can use resistors, potentiometers, non-polarized and polarized capacitors, LEDs, diodes (1S1588, 1N4148), Zener diodes, NPN and PNP transistors (2N3904 and 2N3906 by default), DIP switches, tact switches, and seven-segment displays (FND-500 common cathode, FND-507 common anode).
For ICs, there are more than 30 built-in models, including the NE555, LM358, LM324, 74LS and 74HC logic, and the CD4000 series, plus generic ICs where you only choose the pin count (8, 14, 16, 20, or 24 pins).
How accurate is the simulation?
It calculates the voltage and current at each connection point from a DC analysis, and parts whose state changes over time, such as timers and sequential logic, are updated by advancing time in small steps.
It uses ideal component models, so real-part tolerances, temperature behavior, noise, and high-frequency behavior are not reflected. Transistors are also a simple switch model that turns on by base–emitter voltage, not by current gain (hFE). Use it to check wiring mistakes and signal direction in advance, and confirm high-current or safety-critical circuits by real measurement.
Can I change the board size and supply voltage?
In [Board settings] you can change the size from 17 to 161 holes wide and 13 to 121 holes tall (the default is 62×28 holes). On the [Power] tab in the same place, you set the supply voltage, the internal resistance of the supply, and the maximum current.
Can I use it on a phone or tablet?
The layout adapts to the screen size, and touch gestures such as pinch zoom, long-press to open a menu, and two-finger tap to undo are supported. You can also configure pen input (drawing with the pen auto-wires, and the eraser button switches tools).
That said, a mouse or pen is much easier for precise hole-by-hole wiring.
The 3D view will not open.
The 3D view uses WebGL. Check that hardware acceleration is turned on in a current version of Chrome, Edge, Safari, or Firefox. If 3D cannot be opened, you are returned to the 2D view automatically with a message.
What if I do not like the auto-rewire result?
Auto-rewire applies its result to the board in one go and records it as a single step in the undo history, so one Ctrl+Z returns you to the original wiring. When it finishes, the summary shows which nets changed, which were kept, and which failed.
If it cannot find a result that meets the conditions, or you edit the board while it is running, the result is not applied and the original is left untouched.
If I upload a schematic image, will the board be completed automatically?
No. It is a draft feature that reads parts and connections (nets) from a schematic photo and draws connection hints (a ratsnest) between board pins. Recognition can be wrong, so you must check and fix pin numbers and connections on the board yourself.
Can I save the drawing as an image or PDF?
Image and PDF export are not available right now. Save a board with a share link or a RAW JSON file, and use a screenshot if you need a drawing.
Are there keyboard shortcuts?
Keys that are easy to reach with your left hand are assigned to tools while your right hand stays on the mouse. W is wire, D and J are jumper, A is add part, R is rotate, F is flip the board, and 2 and 3 switch to 2D and 3D views. Ctrl+K searches commands, and pressing ? opens the full list.
Is the circuit I make sent to a server?
Editing and simulation all run inside your browser. Board data is stored on the server (Cloudflare) only when you create a [Share] link. The parts that use outside services, such as fonts and ads, are described in the Privacy Policy and the Ads & Cookies page.
This is my first time soldering perfboard. Where should I start reading?
Read "What Is Perfboard? Types and How to Choose", "Perfboard Soldering Basics", and "Reading a Layout Diagram" in that order, then follow the "Getting Started with Patterndo" guide to build an LED circuit. Checking the layout and wiring in Patterndo before you actually solder greatly reduces mistakes.
I found a bug. I want to suggest a feature.
Please get in touch through the contact page. For bugs, including the browser and operating system you used, the order of your actions, and ideally a share link makes it much faster to reproduce.
If a problem is still unresolved, please use the contact page. Telling us the browser you used and how to reproduce it lets us check much faster.