The Breakdown of the WIFI standards and the Frequency Band

Here’s a breakdown of which standards use Which frequency bands:

Standards Operating on 2.4 GHz Only

802.11: The original standard often called as “Prime” Debuted on 1997 ran exclusively on the 2.4 GHz band, offering up to 2 Mbps using FHSS and DSSS.
802.11b : This standard Ratified in 1999 which Stayed on 2.4 GHz, boosting speeds to 11 Mbps with enhanced DSSS and CCK.
802.11g : This standard was Ratified in 2003 which exclusive to 2.4 GHz, it reached 54 Mbps using OFDM while remaining compatible with 802.11b.

802.11a : This standard was Ratified in 1999 Operated solely on the 5 GHz band, delivering up to 54 Mbps with OFDM to avoid 2.4 GHz interference.
802.11ac : This standard was Ratified in 2013 Known as Wi-Fi 5, it dedicated to 5 GHz, achieving gigabit speeds (over 1 Gbps) with MU-MIMO and wider channels.

802.11n : Ratified in 2009 which is a A major leap, 802.11n introduced dual-band support (2.4 GHz and 5 GHz), hitting up to 600 Mbps with MIMO.
802.11ax : Ratified in 2019 Wi-Fi 6 supports both 2.4 GHz and 5 GHz (plus 6 GHz in Wi-Fi 6E), topping 9 Gbps with OFDMA and enhanced MU-MIMO.
802.11be (Wi-Fi 7): Ratified in 2024 Still emerging as of 2025, Wi-Fi 7 will operate on 2.4 GHz, 5 GHz, and 6 GHz, promising over 30 Gbps with multi-link operation. It inherently supports both 2.4 GHz and 5 GHz.

802.11ax with Wi-Fi 6E : This standard was ratified in 2021 An extension of Wi-Fi 6, it adds 6 GHz support while retaining 2.4 GHz and 5 GHz. Speeds exceed 9 Gbps, and the 6 GHz band offers less interference and wider channels (up to 160 MHz). Devices must be Wi-Fi 6E-certified to use 6 GHz.
802.11be (Wi-Fi 7, Expected ~2024): As of 2025, still rolling out, Wi-Fi 7 supports all three bands—2.4 GHz, 5 GHz, and 6 GHz—with speeds over 30 Gbps. It uses 320 MHz channels, multi-link operation (MLO), and advanced MU-MIMO, making it the most versatile standard yet.