ESP With the Strongest WiFi Signal

I compared WiFi RSSI across three ESP boards I had lying around: an ESP8266 with a PCB trace antenna, an ESP32-D0WDQ6 with a folded PCB antenna sticking up off the module, and an ESP32-D0WD-V3 with a flush trace antenna. The one with the antenna folded up off the module won by ~10-20dB.

Published: Monday, Sep 7, 2026 Last modified: Monday, Sep 7, 2026

I had three random ESP boards on my desk, so I plugged each into a laptop with esptool to find out exactly what they were, and logged the WiFi RSSI each one reported to the same access point.

Three ESP boards side by side next to a ruler: left an ESP8266 with a PCB zigzag trace antenna, middle an ESP32 with its antenna folded up above the module, right an ESP32 with its antenna flush against the module

The same three ESP boards flipped over showing their pin headers and PCB backs, next to a ruler

Board (left to right) Chip (via esptool chip-id) Antenna RSSI
HiLetgo NodeMCU ESP8266EX PCB trace -80 to -9x dBm
ESP32 DevKitC V4 ESP32-D0WDQ6 rev v1.0 Inbuilt, folded up off the module -7x dBm
Generic ESP32 board (AliExpress) ESP32-D0WD-V3 rev v3.1 Inbuilt, flush with the module -80 to -9x dBm

The middle board — the ESP32-D0WDQ6 with its antenna folded up and away from the module rather than lying flat against it — was consistently 10-20dB stronger than the other two. All three boards have a non-detachable, built-in antenna; there’s no U.FL connector or separate rod antenna on any of them. The generic AliExpress board on the right, despite being the newer chip revision (V3.1 vs V1.0), had its antenna trace flush with the module and was one of the weakest performers. I won’t be buying that one again.

Lesson: it’s not about “built-in vs external” — all three boards had a fixed, inbuilt antenna. What mattered was the antenna’s layout and how well it was clear of the ground plane. Cheap unbranded clone boards vary wildly here, so it’s worth checking photos closely (or just measuring RSSI yourself) rather than assuming any ESP32 board’s antenna is as good as any other’s.