Online Circuit Diagram Maker
DCACLab is a circuit diagram maker and circuit builder that opens in your web browser. Drag realistic parts onto the board, wire them together and press Play to watch the circuit work. There is nothing to install.
The lab is limited without an account. Create a free account
What it draws, and what it does not
The lab draws circuits with realistic parts: a battery looks like a battery and a lamp looks like a lamp. Press Symbols in the toolbar and the same circuit switches to standard schematic symbols, in the ANSI or the IEC style. The wires stay where they are, and a saved circuit opens in the view you left it in. Batteries, resistors, capacitors, diodes, LEDs, lamps, switches, fuses, transistors and op-amps have symbols; logic gates, chips and a few other parts keep their realistic look. The lab cannot export a diagram as an image or PDF, so if you need a file for a report, a dedicated schematic editor will suit you. If you want a circuit maker that shows whether your design works, start here.
What you can do
- Place realistic parts. Drag batteries, resistors, capacitors, diodes, LEDs, transistors, switches, lamps, logic gates and more onto the board.
- Wire them up. Drag wires between the parts to connect them.
- Simulate instantly. Press Play and the circuit runs live, then press Pause when you want to stop it.
- Measure it. On desktop, connect an analog multimeter, a digital multimeter, an oscilloscope or a wattmeter. The oscilloscope is not available on phones, and some meters need a plan.
- Switch to symbols. Press Symbols to see the circuit as a schematic, and pick the ANSI or the IEC style.
- Switch to a breadboard. Use the Breadboard toggle to work the way you would on a real bench.
- Choose the wire thickness. Pick a gauge from the AWG list, from 30 to 10, with 22 as the default. It sets the wire's width and resistance, so a thin wire drops more voltage than a thick one at the same current, and it can overheat.
How to draw a circuit diagram
- Open the lab. The Start drawing button opens a new circuit.
- Place the parts. Start with a power source, such as a battery, then drag the other parts onto the board.
- Connect them. Drag wires from part to part until the circuit forms a closed loop.
- Set the values. Select a part and change its properties, such as the voltage of a battery or the resistance of a resistor.
- Press Play and measure. Run the circuit, connect a meter and read the voltage and current. If something looks wrong, press Pause, fix the wiring and run it again.
Example circuits
These public circuits were all built in the lab. Open one to see how the parts are wired, and how it behaves when it runs.
For teachers and classes
Teachers can turn a circuit into a class activity. Create a classroom, share its join link, assign a circuit with a due date and grade what your students hand in. Schools can run their classes under an institutional license.
Frequently asked questions
Is the circuit diagram maker free?
You can try it free, with limits. Without an account, on a computer or tablet, you get one of each part, and you cannot edit values, use switches or read meters. A free account gives you about 10 minutes before those limits apply. Saving a circuit needs a plan.
Do I need to download anything?
No. The lab opens in your web browser, so there is nothing to install. There is no app in the app stores.
Can I simulate the diagram?
Yes. The circuit you draw is the circuit that runs. Press Play to start the simulation and Pause to stop it, and connect a meter to read what the circuit is doing.
Can students use it in class?
Yes. A teacher creates a classroom, shares its join link, assigns a circuit with a due date and grades what students hand in. Teachers can try the free classroom demo: one classroom with room for 30 students for 7 days, counted from when the first student joins (once per teacher). After that, the classroom keeps up to 5 students.
What is the difference between a circuit diagram maker and a circuit simulator?
A circuit diagram maker draws how parts connect. A circuit simulator also works out what the circuit does, such as its voltages and currents. DCACLab is a circuit designer and simulator in one. It shows realistic parts, and its Symbols button redraws the same circuit with standard schematic symbols.
Can I export my diagram as an image or PDF?
No. The lab has no image or PDF export. If you save a circuit, which needs a plan, its Share dialog gives you a link, an embed code and a link to its thumbnail.
Ready to draw your first circuit?
Open the lab, drag in a battery and a lamp, and connect them.