Whats that VHF marine channel that VTAC17 shares its frequency with? Whos probably interfering with our 802.11 b/g/n WiFi router on channel 6? What are the phone privileges for an Amateur Extra licensee on 20 meters? What am I hearing on 46.610 MHz? Somebody with a popular-brand business-band handheld says, "Your communications center can monitor us on channel 15 in our radios," but what frequency is that? FRS channel 15? CB channel 15? Korean CB channel 15? HF Marine channel 1215? Can an amateur radio operator legally use a German "FreeNet" radio? [The answer is no; download the app to see why.] What kind of entity is probably operating on 154.160 MHz?
COMU-F provides ICS Communications Unit leadership (COMLs) and technicians (COMTs) with offline access to these and tens of thousands of other answers. COMU-F contains over 53,000 frequency channels and ranges organized into 470 band plans. You can search for all frequencies within given lower and upper limits (including several predefined limits), and for all frequencies with a designation that is equal to, begins withs, or contains a certain search string. You can look at all band plans, or only enable some, individually or using preset organized groups (like "All Amateur Radio" or "All Personal Radio US").
For each frequency, you see the band plan, designation if any ("Channel 51", "IMTS YJ", etc.), transmit and receive (for channels) or lower and upper (for ranges) frequencies, mode, and access code, and for many, you see the citation supporting the entry and usage notes. If you arent sure what a band plan is, for many you can touch a computer icon and view information about that band plan from the internet (if you have an internet connection). And if you have any problems or find errors in the database, theres a feedback button.