8 November 2026 · Soldr
Wokwi alternative: when you're ready to flash a real ESP32 or Arduino
Wokwi is an online simulator. It is a good one for trying ESP32 and Arduino code before you own the board. When you are ready for real hardware, Soldr covers the next step: you describe the build in plain words, it gives the wiring and code, and it flashes your board from Chrome or Edge. Parts come from Compoden, with delivery across India.
What Wokwi does well
Wokwi's docs describe it as "an online Electronics simulator." They name Arduino, ESP32 and STM32 among the supported boards. The supported-hardware page lists ESP32 variants, Arduino Uno, Nano and Mega, ATtiny85, STM32 and Raspberry Pi Pico boards. It also simulates parts such as sensors, displays, LEDs and motors.
The docs say: "You can't destroy the virtual hardware." That matters when you are learning. A pin mistake or a loop bug costs nothing.
On price, the docs say Wokwi is "free for personal use." The pricing page shows a free Community plan next to paid plans, and a Classroom licence for educators, with the price on quotation. Check that page for current terms.
If you have no board yet, or you want to share a runnable project link, Wokwi is the better choice.
Where a simulator stops
A simulator runs a model of the chip and the parts. It cannot tell you:
- whether the sensor module you bought has the pinout you assumed
- whether your supply can drive the motor
- whether a 5 V signal is about to reach a 3.3 V pin
- whether the board shows up on your laptop's USB port
These questions only appear on the bench. They are also where first builds fail.
What Soldr does
Soldr's site says you describe a device in plain words, and it selects parts, shows how to wire them, writes the code, and flashes supported boards from your browser.
The steps:
- You describe the build, starting with the board and the main parts.
- Soldr gives a pin-by-pin wiring table and a schematic.
- It writes the code and compiles it on its server.
- In Chrome or Edge, you press Flash and pick the serial port.
Boards that flash from the browser include ESP32 (DevKit, S3, C3), Arduino Uno, Nano and Mega. Raspberry Pi Pico also flashes from Chrome or Edge. There is no IDE to install. Boards with CP2102 or CH340 USB chips may need a one-time driver. Flashing needs a laptop; you can plan a build on a phone.
Soldr's safety guide says the wiring and code come from one pin plan, and that it checks logic levels and power. It also says no tool can verify your actual wiring, parts or supply for you. Take that seriously.
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Wokwi vs Soldr
| Feature | Wokwi | Soldr |
|---|---|---|
| What it does | Online electronics simulator | Plans a real build: parts, wiring, code, compile, flash |
| Simulation or real board | Virtual hardware | Real boards flashed over USB |
| Boards | Arduino, ESP32, STM32, Pico and more, simulated | ESP32, Uno, Nano, Mega and Pico flash from the browser |
| Describe in plain words | Not stated in the docs | Yes |
| Parts to buy | None | Parts from Compoden, delivered across India |
| Free option | Free for personal use; free Community plan | Sign in and get 100 credits free. |
Prompts that work for a first real build
Good prompts name the board and give numbers.
- "I want to build a room temperature display with an ESP32 DevKit, a DHT22 sensor and a 0.96 inch OLED."
- "I want to build a small desk clock with an ESP32 that gets the time over WiFi and shows it on an OLED."
- "I want to build a distance meter with an Arduino Uno, an ultrasonic sensor and an I2C LCD."
If you already own a board, say so. For tips, see how to describe a hardware build to AI and ESP32 vs Arduino Uno.
A good order of work
- Prototype the logic in Wokwi if you like. It costs nothing.
- Move to real hardware when the idea is settled.
- Flash a small test sketch before the full code, as the Soldr safety guide suggests.
- Keep the first build low voltage.
Which should you choose?
- Choose Wokwi when you have no hardware, want to share a simulation, or teach a class on a zero parts budget.
- Choose Soldr when you want the real board blinking, reading and displaying, and want the parts and wiring planned for you.
FAQ
What is a Wokwi alternative for real hardware? Soldr. It gives wiring, code and a parts list from a plain-words description, and flashes supported boards from Chrome or Edge. Wokwi is a simulator and uses virtual hardware.
Can I flash an ESP32 from the browser? With Soldr, yes. ESP32 DevKit, S3 and C3 boards flash from Chrome or Edge over USB. There is no IDE to install, though CP2102 or CH340 boards may need a driver.
Is Wokwi free? Wokwi's docs say it is free for personal use. See wokwi.com/pricing for plans.
Does Soldr work on a phone? You can plan a build on a phone. Flashing needs a laptop with Chrome or Edge.
Related
Sources
Read on 2026-11-08.
- Wokwi docs home (online electronics simulator; free for personal use; virtual hardware): https://docs.wokwi.com/ (read 2026-11-08)
- Wokwi supported hardware: https://docs.wokwi.com/getting-started/supported-hardware (read 2026-11-08)
- Wokwi pricing (Community plan, paid plans, Classroom licence by quotation): https://wokwi.com/pricing (read 2026-11-08)
- Soldr home page: https://soldr.ai/ (read 2026-11-08)
- Soldr llms.txt (compile on server, Chrome/Edge flashing, driver note): https://soldr.ai/llms.txt (read 2026-11-08)
- Soldr guide: /blog/is-ai-generated-arduino-code-safe-to-flash (read 2026-11-08)
- Soldr guide: /blog/how-to-describe-a-hardware-build-to-ai (read 2026-11-08)
- Soldr guide: /blog/esp32-vs-arduino-uno (read 2026-11-08)