Wi-Fi 8 (802.11bn) MCS Table: Complete Reference Guide
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Introduction : In Wi-Fi 8 (IEEE 802.11bn), the Modulation and Coding Scheme (MCS) strategy shifts away from simply “going faster” to “being more reliable.” Unlike Wi-Fi 7, which introduced 4096-QAM to break speed records, Wi-Fi 8 maintains the same peak modulation but introduces four new intermediate MCS levels. These new levels are designed to fill the “sensitivity gaps” between existing levels. Let us explore Wi-Fi 8 MCS table including additions made.
Why Wi-Fi 8 introduced new MCS levels
In legacy versions (Wi-Fi 6/7), the jump in signal-to-noise ratio (SNR) required to move from one MCS level to the next could be more than 3 dB.
Problem: If a device’s signal was “almost” good enough for a higher speed, but not quite, it was forced to stay at a much lower speed.
Wi-Fi 8 Solution: By adding MCS 17, 19, 20, and 23, Wi-Fi 8 provides finer granularity. This allows the “Rate Adaptation” algorithm to pick a speed that perfectly matches the current signal quality, improving overall throughput and reducing packet drops.
Wi-Fi 8 MCS Table as defined in IEEE 802.11bn
The folloging table includes the legacy Wi-Fi 7 (EHT) values and the newly introduced Wi-Fi 8 (UHR) “gap-filler” levels.
| MCS Index | Modulation Code Rate | Binary Signaling (5-bit) | Generation / Type |
|---|---|---|---|
| 0 | BPSK 1/2 | [00000] | Legacy |
| 1 | QPSK 1/2 | [00001] | Legacy |
| 17 | QPSK 2/3 | [10001] | New (Wi-Fi 8) |
| 2 | QPSK 3/4 | [00010] | Legacy |
| 3 | 16-QAM 1/2 | [00011] | Legacy |
| 19 | 16-QAM 2/3 | [10011] | New (Wi-Fi 8) |
| 4 | 16-QAM 3/4 | [00100] | Legacy |
| 20 | 16-QAM 5/6 | [10100] | New (Wi-Fi 8) |
| 5 | 64-QAM 2/3 | [00101] | Legacy |
| 6 | 64-QAM 3/4 | [00110] | Legacy |
| 7 | 64-QAM 5/6 | [00111] | Legacy |
| 23 | 256-QAM 2/3 | [10111] | New (Wi-Fi 8) |
| 8 | 256-QAM 3/4 | [01000] | Legacy |
| 9 | 256-QAM 5/6 | [01001] | Legacy |
| 10 | 1024-QAM 3/4 | [01010] | Legacy |
| 11 | 1024-QAM 5/6 | [01011] | Legacy |
| 12 | 4096-QAM 3/4 | [01100] | Legacy |
| 13 | 4096-QAM 5/6 | [01101] | Legacy |
| 14 | BPSK-DCM-DUP 1/2 | [01110] | Legacy (Reliability) |
| 15 | BPSK-DCM 1/2 | [01111] | Legacy (Reliability) |
- To remain backward compatible with Wi-Fi 7, Wi-Fi 8 uses a 5-bit signaling field for the MCS.
- Bit 5 (MSB) = 0: The hardware interprets the remaining 4 bits as the legacy Wi-Fi 7 MCS (0–15).
- Bit 5 (MSB) = 1: The hardware identifies it as a new Wi-Fi 8 UHR MCS level.
Summary : Major Points
- Peak Speed: Wi-Fi 8 doesn’t have a higher “top speed” than Wi-Fi 7 (both peak at MCS 13 with 4096-QAM).
- The “Gap” Logic: Notice where the new levels are placed. For example, MCS 20 (16-QAM 5/6) sits exactly between 16-QAM 3/4 and 64-QAM 2/3.
- Better Adaptation: Devices will now “stutter” less when moving away from a router, as they have more intermediate steps to downshift through.
References
- EEE P802.11bn/D1.0: Amendment 6: Enhancements for ultra-high reliability (UHR).
- Rohde & Schwarz White Paper: Setting new performance standards with IEEE 802.11bn (Version 02.00, 2026).
- IEEE Project Authorization Request (PAR): Amendment to IEEE Standard 802.11-2020 – Ultra-High Reliability.
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