NTPsec

rabbit.wiktel.com

Report generated: Tue Oct 6 04:53:00 2026 UTC
Start Time: Mon Oct 5 04:53:00 2026 UTC
End Time: Tue Oct 6 04:53:00 2026 UTC
Report Period: 1.0 days

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Local Clock Time/Frequency Offsets

local offset plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Time Offset -1,067.000 -637.000 -281.000 -4.000 351.000 709.000 1,708.000 632.000 1,346.000 200.958 8.656 ns -2.933 15.63
Local Clock Frequency Offset -17.103 -17.102 -17.095 -16.959 -16.781 -16.767 -16.765 0.314 0.335 0.102 -16.947 ppm -4.661e+06 7.787e+08

The time and frequency offsets between the ntpd calculated time and the local system clock. Showing frequency offset (red, in parts per million, scale on right) and the time offset (blue, in μs, scale on left). Quick changes in time offset will lead to larger frequency offsets.

These are fields 3 (time) and 4 (frequency) from the loopstats log file.



Local RMS Time Jitter

local jitter plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local RMS Time Jitter 0.000 1.000 1.000 1.000 29.000 77.000 228.000 28.000 76.000 13.844 5.684 ns 3.338 31.59

The RMS Jitter of the local clock offset. In other words, how fast the local clock offset is changing.

Lower is better. An ideal system would be a horizontal line at 0μs.

RMS jitter is field 5 in the loopstats log file.



Local RMS Frequency Jitter

local stability plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local RMS Frequency Jitter 0.000 6.000 10.000 47.000 492.000 708.000 1,482.000 482.000 702.000 161.775 112.513 10e-12 1.78 9.689

The RMS Frequency Jitter (aka wander) of the local clock's frequency. In other words, how fast the local clock changes frequency.

Lower is better. An ideal clock would be a horizontal line at 0ppm.

RMS Frequency Jitter is field 6 in the loopstats log file.



Local Clock Time Offset Histogram

local offset histogram plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Offset -1,067.000 -637.000 -281.000 -4.000 351.000 709.000 1,708.000 632.000 1,346.000 200.958 8.656 ns -2.933 15.63

The clock offsets of the local clock as a histogram.

The Local Clock Offset is field 3 from the loopstats log file.



Server Offsets

peer offsets plot

The offset of all refclocks and servers. This can be useful to see if offset changes are happening in a single clock or all clocks together.

Clock Offset is field 5 in the peerstats log file.



Server Offset 2001:678:8::123 (any.time.nl)

peer offset 2001:678:8::123 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2001:678:8::123 (any.time.nl) -0.828 -0.568 -0.411 0.137 0.847 1.076 1.911 1.258 1.644 0.390 0.167 ms -1.245 4.687

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 2600:2600::199 (ntp2.wiktel.com)

peer offset 2600:2600::199 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2600:2600::199 (ntp2.wiktel.com) -965.582 -926.297 -878.316 -434.075 -192.024 -127.016 -54.886 686.292 799.281 207.071 -481.873 µs -47.32 198.1

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 2600:2600::99 (ntp1.wiktel.com)

peer offset 2600:2600::99 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2600:2600::99 (ntp1.wiktel.com) -582.051 -553.974 -477.110 -40.625 172.870 256.615 273.200 649.980 810.589 198.328 -88.320 µs -8.007 23.26

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 2602:81c:1000:2::604 (time-usw4.crimpac.net)

peer offset 2602:81c:1000:2::604 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2602:81c:1000:2::604 (time-usw4.crimpac.net) 0.302 0.373 0.483 0.786 1.104 1.211 1.251 0.621 0.838 0.184 0.783 ms 44.48 179.8

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 2606:4700:f1::123 (time.cloudflare.com)

peer offset 2606:4700:f1::123 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2606:4700:f1::123 (time.cloudflare.com) -884.675 -850.236 -776.712 -310.599 196.401 264.339 282.958 973.113 1,114.575 295.309 -275.657 µs -13.05 38.71

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 50.205.57.38

peer offset 50.205.57.38 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 50.205.57.38 -154.339 -138.204 -86.588 359.492 582.193 674.229 726.813 668.781 812.433 195.573 318.022 µs 1.484 3.582

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset SHM(0)

peer offset SHM(0) plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset SHM(0) -1,068.000 -638.000 -282.000 -5.000 352.000 710.000 1,709.000 634.000 1,348.000 201.501 8.607 ns -2.939 15.57

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Jitters

peer jitters plot

The RMS Jitter of all refclocks and servers. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 2001:678:8::123 (any.time.nl)

peer jitter 2001:678:8::123 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2001:678:8::123 (any.time.nl) 31.746 40.469 46.354 104.273 397.473 492.759 677.653 351.119 452.290 108.095 145.003 µs 2.825 9.395

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 2600:2600::199 (ntp2.wiktel.com)

peer jitter 2600:2600::199 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2600:2600::199 (ntp2.wiktel.com) 21.212 25.894 32.892 62.733 111.044 137.846 153.081 78.152 111.952 24.144 66.295 µs 11.39 37.25

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 2600:2600::99 (ntp1.wiktel.com)

peer jitter 2600:2600::99 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2600:2600::99 (ntp1.wiktel.com) 13.341 14.117 22.743 43.173 83.358 103.858 127.241 60.615 89.741 18.105 45.956 µs 9.438 32.14

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 2602:81c:1000:2::604 (time-usw4.crimpac.net)

peer jitter 2602:81c:1000:2::604 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2602:81c:1000:2::604 (time-usw4.crimpac.net) 21.988 23.030 32.464 63.877 119.844 182.768 268.224 87.380 159.738 31.097 69.121 µs 7.559 32.53

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 2606:4700:f1::123 (time.cloudflare.com)

peer jitter 2606:4700:f1::123 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2606:4700:f1::123 (time.cloudflare.com) 15.592 23.810 30.855 66.000 330.325 428.735 450.415 299.470 404.925 82.245 90.052 µs 3.004 11.07

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 50.205.57.38

peer jitter 50.205.57.38 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 50.205.57.38 0.022 0.027 0.034 0.058 0.113 47.078 47.109 0.078 47.051 4.774 0.553 ms 6.3 65.2

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter SHM(0)

peer jitter SHM(0) plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter SHM(0) 0.000 0.000 1.000 3.000 50.000 315.000 1,141.000 49.000 315.000 53.149 16.182 ns 5.696 69.99

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Summary


Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Frequency Offset -17.103 -17.102 -17.095 -16.959 -16.781 -16.767 -16.765 0.314 0.335 0.102 -16.947 ppm -4.661e+06 7.787e+08
Local Clock Time Offset -1,067.000 -637.000 -281.000 -4.000 351.000 709.000 1,708.000 632.000 1,346.000 200.958 8.656 ns -2.933 15.63
Local RMS Frequency Jitter 0.000 6.000 10.000 47.000 492.000 708.000 1,482.000 482.000 702.000 161.775 112.513 10e-12 1.78 9.689
Local RMS Time Jitter 0.000 1.000 1.000 1.000 29.000 77.000 228.000 28.000 76.000 13.844 5.684 ns 3.338 31.59
Server Jitter 2001:678:8::123 (any.time.nl) 31.746 40.469 46.354 104.273 397.473 492.759 677.653 351.119 452.290 108.095 145.003 µs 2.825 9.395
Server Jitter 2600:2600::199 (ntp2.wiktel.com) 21.212 25.894 32.892 62.733 111.044 137.846 153.081 78.152 111.952 24.144 66.295 µs 11.39 37.25
Server Jitter 2600:2600::99 (ntp1.wiktel.com) 13.341 14.117 22.743 43.173 83.358 103.858 127.241 60.615 89.741 18.105 45.956 µs 9.438 32.14
Server Jitter 2602:81c:1000:2::604 (time-usw4.crimpac.net) 21.988 23.030 32.464 63.877 119.844 182.768 268.224 87.380 159.738 31.097 69.121 µs 7.559 32.53
Server Jitter 2606:4700:f1::123 (time.cloudflare.com) 15.592 23.810 30.855 66.000 330.325 428.735 450.415 299.470 404.925 82.245 90.052 µs 3.004 11.07
Server Jitter 50.205.57.38 0.022 0.027 0.034 0.058 0.113 47.078 47.109 0.078 47.051 4.774 0.553 ms 6.3 65.2
Server Jitter SHM(0) 0.000 0.000 1.000 3.000 50.000 315.000 1,141.000 49.000 315.000 53.149 16.182 ns 5.696 69.99
Server Offset 2001:678:8::123 (any.time.nl) -0.828 -0.568 -0.411 0.137 0.847 1.076 1.911 1.258 1.644 0.390 0.167 ms -1.245 4.687
Server Offset 2600:2600::199 (ntp2.wiktel.com) -965.582 -926.297 -878.316 -434.075 -192.024 -127.016 -54.886 686.292 799.281 207.071 -481.873 µs -47.32 198.1
Server Offset 2600:2600::99 (ntp1.wiktel.com) -582.051 -553.974 -477.110 -40.625 172.870 256.615 273.200 649.980 810.589 198.328 -88.320 µs -8.007 23.26
Server Offset 2602:81c:1000:2::604 (time-usw4.crimpac.net) 0.302 0.373 0.483 0.786 1.104 1.211 1.251 0.621 0.838 0.184 0.783 ms 44.48 179.8
Server Offset 2606:4700:f1::123 (time.cloudflare.com) -884.675 -850.236 -776.712 -310.599 196.401 264.339 282.958 973.113 1,114.575 295.309 -275.657 µs -13.05 38.71
Server Offset 50.205.57.38 -154.339 -138.204 -86.588 359.492 582.193 674.229 726.813 668.781 812.433 195.573 318.022 µs 1.484 3.582
Server Offset SHM(0) -1,068.000 -638.000 -282.000 -5.000 352.000 710.000 1,709.000 634.000 1,348.000 201.501 8.607 ns -2.939 15.57
Summary as CSV file


Glossary:

frequency offset:
The difference between the ntpd calculated frequency and the local system clock frequency (usually in parts per million, ppm)
jitter, dispersion:
The short term change in a value. NTP measures Local Time Jitter, Refclock Jitter, and Server Jitter in seconds. Local Frequency Jitter is in ppm or ppb.
kurtosis, Kurt:
The kurtosis of a random variable X is the fourth standardized moment and is a dimension-less ratio. ntpviz uses the Pearson's moment coefficient of kurtosis. A normal distribution has a kurtosis of three. NIST describes a kurtosis over three as "heavy tailed" and one under three as "light tailed".
ms, millisecond:
One thousandth of a second = 0.001 seconds, 1e-3 seconds
mu, mean:
The arithmetic mean: the sum of all the values divided by the number of values. The formula for mu is: "mu = (∑xi) / N". Where xi denotes the data points and N is the number of data points.
ns, nanosecond:
One billionth of a second, also one thousandth of a microsecond, 0.000000001 seconds and 1e-9 seconds.
percentile:
The value below which a given percentage of values fall.
ppb, parts per billion:
Ratio between two values. These following are all the same: 1 ppb, one in one billion, 1/1,000,000,000, 0.000,000,001, 1e-9 and 0.000,000,1%
ppm, parts per million:
Ratio between two values. These following are all the same: 1 ppm, one in one million, 1/1,000,000, 0.000,001, and 0.000,1%
‰, parts per thousand:
Ratio between two values. These following are all the same: 1 ‰. one in one thousand, 1/1,000, 0.001, and 0.1%
refclock:
Reference clock, a local GPS module or other local source of time.
remote clock:
Any clock reached over the network, LAN or WAN. Also called a peer or server.
time offset:
The difference between the ntpd calculated time and the local system clock's time. Also called phase offset.
σ, sigma:
Sigma denotes the standard deviation (SD) and is centered on the arithmetic mean of the data set. The SD is simply the square root of the variance of the data set. Two sigma is simply twice the standard deviation. Three sigma is three times sigma. Smaller is better.
The formula for sigma is: "σ = √[ ∑(xi-mu)^2 / N ]". Where xi denotes the data points and N is the number of data points.
skewness, Skew:
The skewness of a random variable X is the third standardized moment and is a dimension-less ratio. ntpviz uses the Pearson's moment coefficient of skewness. Wikipedia describes it best: "The qualitative interpretation of the skew is complicated and unintuitive."
A normal distribution has a skewness of zero.
upstream clock:
Any server or reference clock used as a source of time.
µs, us, microsecond:
One millionth of a second, also one thousandth of a millisecond, 0.000,001 seconds, and 1e-6 seconds.



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