Fingerprint Sensor AS608 - A Beginner's Guide
One touch can replace keys. This project uses an optical fingerprint sensor to enroll users and then grant access with a quick scan.
read tutorial →
ESP-01 512 KB — The Original Ultra-Compact WiFi Serial Module
The ESP-01 512 KB WiFi Serial Transceiver Module is the module that launched the ESP8266 revolution. At under 15 × 25 mm, it is still one of the smallest ways to give any UART-capable microcontroller access to a full 802.11 WiFi network using simple AT commands — no stack, no library, no extra hardware required on the host side.
With 512 KB of flash, it is designed primarily for AT command operation — acting as a WiFi modem for Arduino, STM32, PIC, or any serial-capable board. If you need standalone programmable firmware, the ESP-01S (1 MB) gives you more headroom.
ESP-01 (512 KB) vs ESP-01S (1 MB) — which should you choose?
| Feature | ESP-01 (this product) | ESP-01S |
|---|---|---|
| Flash memory | 512 KB | 1 MB |
| Best use | AT command WiFi modem for host MCU | AT commands + standalone firmware |
| MicroPython capable | Tight fit — not recommended | ✅ Yes, comfortably |
| GPIO pins | 2 (GPIO0, GPIO2) | 2 (GPIO0, GPIO2) |
| Best for | Budget AT-command builds, simple WiFi add-ons | New designs requiring custom firmware |
Key features
- Ultra-compact: ~14 × 24 mm — fits in the tightest enclosures
- AT command interface: Simple serial protocol — easy to implement on any MCU
- TCP/IP stack onboard: HTTP, TCP, UDP all handled internally
- Station + AP modes: Connect to WiFi or create a hotspot
- 2 GPIO pins: For simple I/O alongside WiFi duties
- 3.3V operation: Use with a proper 3.3V supply (not directly from 3.3V Arduino pin — needs ~200 mA)
Technical specifications
| Core Chip | ESP8266EX |
|---|---|
| Flash Memory | 512 KB SPI Flash |
| GPIO Pins | 2 (GPIO0, GPIO2) |
| WiFi Standard | 802.11 b/g/n, 2.4 GHz |
| Interface | UART AT commands, 115200 baud default |
| Operating Voltage | 3.0V – 3.6V |
| Operating Current | ~80 mA average, 200 mA peak |
| Dimensions | ~14.3 × 24.8 mm |
Frequently Asked Questions
Can the Arduino 3.3V pin power this? No. The ESP-01 can draw up to 200 mA at peak, more than the Arduino's 3.3V regulator can supply. Use a dedicated 3.3V supply (LM1117 or AMS1117-3.3).
Can I run custom code on this without a host MCU? Technically yes, but 512 KB is very limited. For standalone code, choose the ESP-01S (1 MB) or a full NodeMCU board.
What AT commands does it support? Standard Espressif AT command set — AT+CWJAP (join AP), AT+CIPSTART (open TCP), AT+CIPSEND (send data), and more.
Manila stock. Order before 16:00 PHT, ships today via J&T or LBC. Provincial: 1–3 working days.
Schools / class POs: we accept Purchase Orders for accredited schools and universities. contact us with your PO details.
Returns: 7-day inspection window for DOA units. Email proof of issue and we ship a replacement.
Customers also bought
Build with this board
Thumb Joystick - A Beginner's Guide
Wire a joystick to your Arduino, read X/Y, then print UP / DOWN / LEFT / RIGHT to the serial monitor.
read tutorial →Motor Drive (BTS7960 43A) - A Beginner's Guide
Bench-test a 43 A motor driver before wiring the full project. Catches weak power, mis-pinning, and dead boards before they cost you time.
read tutorial →Raspberry Pi Pico (RP2040) - A Beginner's Guide
Coming from UNO and the Pico won't show a COM port? Here's the BOOTSEL trick, the driver fix, and the first sketch that actually works.
read tutorial →Notes from the bench
Ask the community
Project Showcase — show what you built
Share what you built. Photos, BOM, what worked, what didn't.
view thread →How to ask a good question (and actually get answers)
Symptom + what you tried + clear photo = answers within hours.
view thread →ESP32 brownout when wiring a sensor — fixes that worked
Brownout reset when adding a sensor? Notes on supply decoupling and GPIO checks.
view thread →First Arduino — sketch upload error, what to try?
Upload failing on your first Uno? Driver, COM port, board match — checklist inside.
view thread →