ESP8266 vs ESP32 vs ESP32-S2 vs ESP32-C3

Short name	ESP32	ESP32-C3	ESP32-C3-WROOM-02U	ESP32-S2	ESP8266	ESP8285
Description		ESP32-C3 is pin-compatible with ESP8266. It has a single core RISC-V 32-bit CPU @160 MHz and includes 400 kB of SRAM and 384 kB of flash built-in.				The ESP8285 is similar to the ESP8266, but has built-in 1 MiB of flash.
Website	espressif.com/...	espressif.com/...	espressif.com/...	espressif.com/...	espressif.com/...	espressif.com/...
Release date	2016	2020	2021	2019	2014	2016
Product details
CPU	Tensilica Xtensa LX6 32 bit Dual-Core @ 160 / 240Mhz	RISC-V 32-bit Single-Core @ 160 MHz	32-bit RISC-V single-core processor	Tensilica Xtensa LX7 32 bit Single-Core @ 240Mhz	Tensilica LX106 32 bit @ 80 MHz (up to 160 MHz)	Tensilica LX106 32 bit @ 80 MHz (up to 160 MHz)
Coprocessor	ULP			ULP (RISC-V)
RAM	520 KB	400 KB		320 KB	50 KB less than	160 KB
ROM (Flash)	448 KB	384 KB		128 KB	0 use external SPI flash	1,024 KB
UART	3	2	2	2	2	2
SPI	Yes 4	Yes 3	Yes 3	Yes 4 (OSPI)	Yes 2	Yes 2
Wi-Fi	Yes 802.11b/g/n	Yes 802.11b/g/n	Yes 802.11b/g/n	Yes 802.11b/g/n	Yes 802.11b/g/n (max 65Mbps)	Yes 802.11b/g/n (max 65Mbps)
Bluetooth®	Yes 4.2 BR/EDR + BLE	Yes 5.0 + BLE	Yes 5.0 BLE	No	No	No
USB Host	No	No		Yes	No	No
Ethernet (LAN, RJ45)	Yes 10/100Mbps	No		No	No	No
RTC Memory	16 KB	8 KB	8 KB	16 KB
External SRAM	8 MB up to			128 MB up to		16 MB up to
External Flash	16 MB up to			1 GB up to	16 MB up to
ESP-MESH	Yes	Yes		Yes	Yes	Yes
CAN	Yes v2.0				No
GPIO	34	22 (up to)	15 (up to)	43	17 (up to)	17 (up to)
Hall effect sensor	Yes	No	No	No	No	No
Temperature sensor	Yes	Yes	Yes	Yes	No	No
Touch sensors	10		No	14	No	No
I²C	Yes up to 2	Yes up to 1	Yes up to 1	Yes up to 2	Yes up to 1	Yes up to 1
I2S	2	1	1	1	2	2
ADC	Yes 12 bit SAR ADC up to 18 channels	Yes 2 × 12-bit SAR ADCs, up to 6 channels	Yes 2 × 12-bit ADC, up to 6 channels	Yes 12 bit SAR ADC up to 20 channels	Yes 10 bit	Yes 10 bit
DAC	Yes 8 bit up to 2 channels		No	Yes 8 bit up to 2 channels	No	No
PWM	Yes up to 8	Yes up to 6		Yes 8	Yes 4	No
SDMMC	Yes			No	No	No
RMT (remote control)	Yes			Yes	No	No
LCD Interface	No	No		Yes	No	No
Camera Interface	No	No	No	Yes	No	No
Secure flash	1024-bit OTP secure boot	4096-bit OTP		4096-bit OTP secure boot
Cryptography support	AES, SHA-2, RSA, ECC, RNG	AES-128/256, RSA Accelerator, SHA Accelerator, Random Number Generator (RNG), HMAC		AES-128/192/256, SHA-2, RSA, RNG, HMAC, Digital Signature
Deep sleep consumption	10 µA, Yes		5 µA	5 µA	20 µA, Yes	20 µA
Dimensions
Height	6 mm	5 mm	18 mm	7 mm	5 mm	5 mm
Width	6 mm	5 mm	20 mm	7 mm	5 mm	5 mm

Comparison of Baofeng HT radios. Please contribute if you are able. I am trying to get as much information as possible directly from the Baofeng manuals...

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