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KiwiSDR Monitor

This app continuously monitors your KiwiSDR receiver(s) and displays / notifies when a user tunes in or changes the frequency.

For Windows and macOS. Please click on images to view them full sized.

Free To Try!

Not sure you're ready to buy KiwiSDR Monitor? You can download a fully featured copy to try out, before you buy it.

Download a copy for Windows 8, 10, 11: Version 2.4.0 (September 5, 2023)

Download a copy for macOS: Version 2.4.0 (September 5, 2023)

Buy Your Copy of KiwiSDR Monitor Today

$19.99 Registration code sent by email, software download

KiwiSDR Monitor is only $19.99, which entitles you to all updates and new versions released over the next full year, free of charge, which of course you can continue to use forever.

Instructions / Use:

In the main view, you are presented with a list of all the receivers for your KiwiSDR, and their status, if they are in use the tuned frequency, mode, who is tuned in, and for how long they have been connected.

If you have configured more than one KiwiSDR, you will see information for each of them. You can adjust the size of the window if you wish, so all entries are visible.


macOS users: Due to Apple's "App Translocation" nonsense, you should move your downloaded copy of KiwiSDR Monitor to another location, out of your Downloads directory, before running it.

Initially, you will be presented with one entry, no doubt with incorrect information for your setup.

Set the local IP Address and port number for your KiwiSDR (on your LAN, not the public/internet address).

If Notify is checked, you will get an alert each the a user changes frequency, if the app is not in the foreground.

If Save is checked, logged information about receiver usage is written to two sets of log files, see below for details.

The refresh rate specifies how often each KiwiSDR is polled.

You may not wish to get notifications for frequency changes you make. You can use the Ignore IP field to enter a partial substring for an IP address range, addresses matching this (from the left side of their full IP address will be ignored.

If you need to create an additional configuration line for another KiwiSDR, push the Add button, or right click and select Add.

If you want to delete an entry, right click on it and select Delete.

Press the Update button after making changes.

If you don't want to get notifications for some frequency ranges you can create a plain text file (not a .doc or .rtf or anything else, plain text) called kiwimonitor-ignore.txt and place it in the documents directory for your user account. Don't know where that is? Select Location Of Ignore File from the File menu. The contents should look something like this:


Log files:
If Save is checked, logged information about receiver usage is written to two sets of log files, each in a slightly different format, one set for each KiwiSDR configured:
LOGn.TXT - where n is the KiwiSDR number (1, 2, 3, ...)
LOGDATAn.TXT - where n is the KiwiSDR number (1, 2, 3, ...)

These files are written to the same directory where KiwiSDR Monitor is located. The first format is self-explanatory.

The second format writes several tab delimited fields for each entry:
receiver number
user name
user location
user IP address
timestamp for when they tuned in
timestamp for when they tuned out


Go to the graphs tab. Tapping the space bar will alternate between graphing the past 24 hours, 7 days, and 30 days. If the graphs do not advance, try hitting the tab key first, so the graphs get user input focus. Clicking on a graph will copy it to the clipboard so you can paste it elsewhere. Due to the way usage data is generated, user connections are not counted until the user has logged out or changed frequency, so active connections are not included. Note that due to how receiver usage is counted, the graphs should be used as a rough approximation of usage, not exact. Remember that the Save box next to a Kiwi, in the Setup tab, needs to be checked, so usage data is saved, if you want to see graphs.


Get notified when a user tunes into a frequency or range of frequencies.

Click the Add button to add a new row to the list. Change the frequency, use kHz. If the user tunes to the specified frequency +/- 1 kHz you will get a notification. If you want to get alarms for a range, use a dash between the lower and upper frequency, without a space. For example: 6950-6990

Make sure you check the enable box for alarms you wish to receive notifications for, and that you click the Update button when done modifying the list, or your changes will neither be used, nor saved!

Right click on an entry to delete it.


Leave the first text field blank if you want to see all usage, otherwise enter in a filter substring.

Select IP Address or User Name from the next Popup menu, this specifies which field is used to aggregate the usage (and also which field to filter on, optionally)

Select either all KiwiSDRs or just one if you have more than one.

Enter in a date range or leave blank for all dates. I find that mm/dd/yyyy works for the date format, international users may need to experiment to see what localized format works for them.

Push the Generate button. You can click on the list headings to sort the results.


Click on this tab to see a list of all known KiwiSDRs worldwide, ranked by most recent Signal to Noise Ratio (SNR) score. If the list does not appear (which sometimes happens due to networking issues) go to another tab panel and then back to it, to request again. You can search for a particular KiwiSDR and advance the list to the first one matching the characters you have typed. The Next and Prev buttons can be used to move through multiple matching KiwiSDRs.

Double click on an entry to be taken to that KiwiSDR in your default web browser.

Right click and select S/R Ratio Graph to see a graph of the SNR scores for that KiwiSDR. If the graph is blank, the KiwiSDR is probably running an old software version.


Display SNR graphs for all of your monitored KiwiSDRs. Use the popup menu to switch between KiwiSDRs.

Email your comments and questions to

Last modified September 5, 2023