FortiGate 400G
164 Gbps firewall with 25GE SFP28 optics — the mid-range entry point
- Threat protection
- 13 Gbps
- Firewall throughput
- 164 Gbps
- IPsec VPN
- 55 Gbps
- Concurrent sessions
- 28 Million
Front panel
- SFP cage
- RJ45 copper
The 400G is a fourfold jump in firewall throughput over the 200G, to 164 Gbps, and introduces 25GE SFP28 optics. It delivers 13 Gbps threat protection, 11.5 Gbps SSL inspection and 28 million concurrent sessions across 34 interfaces.
Read this model carefully against the 700G. They share identical interfaces and identical 164 Gbps firewall throughput, but the 700G does twice the threat protection (26 vs 13 Gbps) and 38 Gbps of IPS against 25. If your traffic is mostly forwarded rather than deeply inspected, the 400G is the value pick; if you inspect heavily, the 700G is the better box and the price difference is usually justified.
Highlights
- 164 Gbps firewall throughput, 55 Gbps IPsec VPN
- 4x 25GE SFP28 plus 4x 10GE SFP+ optics
- 28 million sessions, 5,000 concurrent SSL VPN users
- Manages 96 FortiSwitches and 512 FortiAPs
Typical deployments
- Data-centre edge where forwarding matters more than inspection depth
- Large campus core with 25GE uplinks
- Sites needing 5,000 concurrent SSL VPN users
The numbers, with their conditions
Every figure below is Fortinet's own, with the test conditions it was measured under.
Performance
Fortinet's published figures. Firewall throughput is measured on UDP with no inspection enabled — size your deployment on threat protection throughput instead, which is measured with firewall, IPS, application control and malware protection all running against an enterprise traffic mix.
| Firewall throughput (1518 / 512 / 64 byte UDP) | 164 / 163 / 145 Gbps |
|---|---|
| IPsec VPN throughput (512 byte)IPsec VPN performance test uses AES256-SHA256. | 55 Gbps |
| IPS throughput (enterprise mix)IPS, application control, NGFW and threat protection are measured with logging enabled. | 25 Gbps |
| NGFW throughput (enterprise mix)NGFW performance is measured with firewall, IPS and application control enabled, enterprise mix traffic. | 14 Gbps |
| Threat protection throughput (enterprise mix)Threat protection performance is measured with firewall, IPS, application control and malware protection enabled, enterprise mix traffic. | 13 Gbps |
| SSL inspection throughput (IPS, avg. HTTPS)SSL inspection performance values use an average of HTTPS sessions of different cipher suites. | 11.5 Gbps |
| Application control throughput (HTTP 64K) | 50 Gbps |
| Firewall latency | 2.51 µs |
Capacity
| Concurrent sessions | 28 Million |
|---|---|
| New sessions / second | 580,000 |
| Firewall policies | 10,000 |
| Max gateway-to-gateway IPsec tunnels | 2,000 |
| Max client-to-gateway IPsec tunnels | 50,000 |
| SSL VPN throughput | 6.1 Gbps |
| Concurrent SSL VPN users (recommended max, tunnel mode) | 5,000 |
| Virtual domains (default / max) | 10 / 50 |
Security Fabric capacity
How much of the rest of the Fabric this model manages directly, with no separate controller.
| Max managed FortiAPs (total / tunnel) | 512 / 256 |
|---|---|
| Max managed FortiSwitches | 96 |
| Max FortiTokens | 5,000 |
Hardware
| Interfaces | 4x 25GE SFP28, 4x 10GE SFP+, 16x GE SFP, 8x 5GE RJ45, 1x 2.5GE RJ45, 1x GE RJ45 |
|---|---|
| Local storage | 960 GB (401G) |
| Power supplies | Dual AC PS |
| Form factor | 1 RU |
| Variants | — |
Sources
- Fortinet Product Matrix — FortiGate Network Security Platform (July 2026) — retrieved 2026-09-01
Reproduced from Fortinet published documentation and subject to change without notice. Where a figure is load-bearing for your design, ask us to confirm it in writing before you order — we will.
Buyers also compare
FortiGate 700G
Twice the 400G's inspected throughput on the same interfaces
FortiGate 200G
11 million sessions and 27.8 Gbps application control in 1 RU
FortiGate 900G
1 RU with ultra-low-latency ports and 74.8 Gbps application control