WiFi 6 vs WiFi 5: throughput, OFDMA, latency — the technical comparison
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You have a WiFi 5 router that "works fine," but your network slows down as soon as multiple devices connect simultaneously. Your 4K box lags during video calls, your IoT devices saturate the channel, your phone struggles at the edge of the room. The problem isn't necessarily throughput — it's the architecture.
WiFi 6 (802.11ax) isn't WiFi 5 (802.11ac) with a higher number. It's a change in radio channel access method, designed for dense networks. This guide explains concretely what changes, what you really gain, and when the upgrade is worth it.
WiFi 6 is designed for 100 devices on a network. WiFi 5 was designed for 10. That's the fundamental difference.
802.11ac vs 802.11ax — both standards in brief
WiFi 5 (IEEE 802.11ac) was released in 2013 (Wave 1) then 2016 (Wave 2). It operates only on the 5 GHz band and introduced downlink MU-MIMO and 160 MHz channels. It's the standard still equipping the majority of French internet boxes and devices sold between 2016 and 2021.
WiFi 6 (IEEE 802.11ax) was finalized in 2021. It operates on the 2.4 GHz and 5 GHz bands simultaneously — WiFi 6E adds the 6 GHz band. It replaces OFDM with OFDMA, improves MU-MIMO (uplink included), and introduces two mechanisms absent from WiFi 5: BSS Coloring and TWT.
| Criterion | WiFi 5 (802.11ac) | WiFi 6 (802.11ax) |
|---|---|---|
| IEEE standard | 802.11ac | 802.11ax |
| Frequency bands | 5 GHz only | 2.4 GHz + 5 GHz (6E: +6 GHz) |
| Max theoretical throughput | 3.5 Gbps (Wave 2) | 9.6 Gbps |
| Max modulation | 256-QAM | 1024-QAM |
| Channel access | OFDM (one device at a time) | OFDMA (multiple devices simultaneously) |
| MU-MIMO | DL only, 4 streams max | DL + UL, 8 streams max |
| BSS Coloring | No | Yes |
| TWT (power saving) | No | Yes |
| Spectral efficiency | Reference | +37% approx. |
| Latency in dense networks | High under load | Reduced by 75% (Wi-Fi Alliance) |
| Max channel | 160 MHz | 160 MHz (same, gain via OFDMA) |
Theoretical and real throughput: 3.5 vs 9.6 Gbps
The "9.6 Gbps" figure for WiFi 6 is calculated for an ideal configuration: 8 spatial streams × 1024-QAM × 160 MHz channel. In practice, no consumer router deploys all 8 streams simultaneously. High-end WiFi 6 routers achieve 4 streams (2 × 2.4 GHz + 2 × 5 GHz), or about 4–5 Gbps of aggregated capacity.
What matters more than peak throughput is the real throughput per device under load. On WiFi 5, when 10 devices connect, they compete for the channel via OFDM: only one speaks at a time, the others wait. On WiFi 6, OFDMA lets multiple devices transmit simultaneously on distinct sub-channels — per-device throughput stays stable even when the network is saturated.
What you'll observe in practice
On a network of 5–10 light devices, WiFi 6 brings 30–40% additional throughput vs WiFi 5. On a network of 30+ devices (open space, dense apartment, meeting room), the gain can reach 200–300% thanks to OFDMA — not because WiFi 6 is "faster," but because it manages contention better.
OFDMA: the true revolution of WiFi 6
OFDMA (Orthogonal Frequency Division Multiple Access) is the most important change between the two generations. To understand why, let's recall how WiFi 5 works.
On WiFi 5, a radio channel (e.g. 80 MHz) is allocated entirely to a single device at a time. If your smartphone sends a 2 KB email, it monopolizes the channel for a few milliseconds — during which your smart TV, your bulbs and your tablet wait. The more devices there are, the longer the queue gets, the more latency climbs.
On WiFi 6, this same channel is divided into Resource Units (RU) — smaller sub-channels. The access point distributes them simultaneously to multiple devices based on their needs. The 2 KB email gets a small RU, the 4K video stream gets a large RU — everything happens in parallel on the same frame.
The concrete result: average latency under load drops by 75% according to the Wi-Fi Alliance. On an office network with 50 active devices, the difference between a smooth video call and dropouts often plays out here.
Improved MU-MIMO: from 4 streams to 8 streams, and uplink included
MU-MIMO (Multi-User Multiple Input Multiple Output) already existed in WiFi 5 Wave 2 — but only for downlink (DL), and limited to 4 simultaneous streams. WiFi 6 extends it to uplink (UL) and doubles capacity to 8 simultaneous streams.
Concretely, a WiFi 6 router can talk simultaneously to 8 different devices in both directions. This is particularly useful for video calls, online gaming and cloud backups — all situations where upload is as critical as download.
Elfcam equipment for deploying WiFi 6
- Mesh WiFi 6 Router AX3000 — 2.5 Gb WAN port, ideal for Freebox Ultra and Orange Livebox 6
- Outdoor WiFi 6 Access Point AX3000 — IP67, PoE+ powered, for gardens and difficult zones
- WiFi 6 Repeater AX3000 — dual-band 2.4/5 GHz, compatible with all boxes
BSS Coloring and TWT: interference and battery life
Two mechanisms specific to WiFi 6 often go unnoticed but have a real impact in dense environments.
BSS Coloring — reducing interference between neighboring networks
In an apartment building or open space, dozens of WiFi networks overlap on the same channels. On WiFi 5, a device that detects a signal from a neighboring network waits before transmitting — even if that signal isn't meant for it. This is the co-channel interference problem.
BSS Coloring adds a "color marker" (an identifier) in each frame. A WiFi 6 device that receives a frame colored differently from its network ignores it and transmits anyway. Result: fewer needless waits, better channel utilization in high-density network environments.
TWT — power saving for IoT devices
TWT (Target Wake Time) lets the access point and devices negotiate precise wake windows. A connected bulb that only needs to communicate once per second can stay in deep sleep between exchanges instead of constantly scanning the channel.
The impact is twofold: significantly improved IoT device battery life (up to 7× according to Wi-Fi Alliance), and fewer "active" devices simultaneously on the channel, which further relieves contention.
WiFi 6E and the 6 GHz band: the logical extension
WiFi 6E is an extension of WiFi 6 that adds the 6 GHz band (5.925–7.125 GHz), available in France since 2021 on certain certified devices. This band offers up to 1200 MHz of additional spectrum — that's 7 non-overlapping 160 MHz channels, versus 2 in the 5 GHz band.
The 6 GHz band is currently uncrowded: few older devices use it, no microwaves or Bluetooth devices on this range. It's the ideal space for very low-latency applications: gaming, VR/AR, 8K video streams. The range is slightly lower than the 5 GHz band (higher absorption), making it a complementary technology rather than a replacement.
WiFi 6E on 6 GHz is like opening a new empty highway next to a saturated ring road. The speed isn't higher, but traffic flows without congestion.
And WiFi 7 (802.11be)?
WiFi 7 standardizes Multi-Link Operation (MLO) — a device can simultaneously use multiple bands (2.4 + 5 + 6 GHz) to combine throughputs and automatically switch in case of interference. Theoretical throughput: 46 Gbps. The WiFi 7 Intel BE200 card available at Elfcam is one of the first to support MLO on PC.
Should you migrate to WiFi 6 in 2026?
The answer depends on your context, not the number on the box.
Migration recommended if: you have more than 15 devices connected simultaneously, your network slows in the evening or when multiple users are present, you're deploying cameras or IoT sensors in large numbers, or you're in an apartment building with many neighboring networks on the same channels.
Migration optional if: you have fewer than 10 devices, your current WiFi 5 box satisfies you, and your internet connection is limited to 1 Gbps or less — in that case, your ISP latency will be the bottleneck well before your WiFi.
One important point: WiFi 6 is backward compatible with all WiFi 4 and WiFi 5 devices. You don't need to replace your terminals to benefit from a WiFi 6 router — older devices continue to work, but don't use OFDMA or TWT until they support 802.11ax.
Complete your WiFi 6 network
- Elfcam PoE Switch — to power your WiFi 6 access points without dedicated mains cabling
- Home fiber network — fiber backbone to link your access points without throughput loss
- Mesh WiFi vs repeater guide — which system to choose to cover the whole house
