How the grade works

PeakHour works out the grade with fixed rules. The same measurements always give the same grade, whether or not Apple Intelligence is available. The AI only writes the explanation; it never sets the grade.

What the grade counts

The grade counts five measurements:

• Latency — the round trip from this Mac to the internet.
• Jitter — how much the latency varies.
• Packet Loss — the share of data that doesn’t arrive.
• Max Measured Speed — the download speed from the last speed test.
• Responsiveness Under Load — round trips per minute (RPM) while the link is busy.

Each one lands in a band:

	Excellent	Good	Fair	Poor
Latency	< 30 ms	30–60 ms	60–100 ms	≥ 100 ms
Jitter	< 10 ms	10–30 ms	30–50 ms	≥ 50 ms
Packet Loss	< 0.5%	—	0.5–2%	≥ 2%
Speed	≥ 500 Mb/s	50–500 Mb/s	25–50 Mb/s	< 25 Mb/s
Responsiveness	≥ 1,000 RPM	500–1,000 RPM	200–500 RPM	< 200 RPM

No packet loss at all shows as Perfect.

Speed and responsiveness come from the network quality test. Until a test has run, the grade leaves responsiveness out and treats speed as Good.

The grade also watches for:

• A weak Wi-Fi signal — −75 dBm or weaker.
• A busy link — traffic above 90% of the speed that the last test measured, in either direction.
• Monitors that do not answer — some of the sites or your ISP’s gateway stop answering while others still do.

From bands to a grade

Grade	When
A+	Every measurement is Excellent, and nothing else holds the grade back.
A	Every measurement is Good or better, and nothing else holds the grade back.
B+	Every measurement is Good or better, with one concern such as a weak Wi-Fi signal or a busy link.
B	A measurement is Fair, or some monitors do not answer.
C	A measurement is Poor, or there are two or more concerns at once.
D	Your ISP’s gateway does not answer, or a Poor measurement comes with two or more concerns.
F	No internet site answers.

The concerns are: a weak Wi-Fi signal, a busy link, monitors that do not answer, packet loss of 0.5% or more, latency over 100 ms, and jitter over 50 ms.

Every grade below an A has at least one reason under Issues identified on the Your Network page. An A or A+ has none.

What the grade leaves out

A problem with a single site — for example one slow or unsteady service while the others are fine — does not lower your grade. It is a problem on the route to that site, not on your connection, and you can’t fix it from home. The Advisor lists it under Issues outside your network on The Internet page instead.