• ●Where does this data come from?
  Two places. The FCC publishes its entire amateur license and application databases as weekly files, with daily change files in between (the "ULS public access files"). W5ZQ keeps a full copy of both on Cloudflare and applies each daily file as soon as the FCC posts it, normally around 7 AM Central the morning after the activity. The FCC also runs the public ULS search site, which shows new applications within minutes of filing; W5ZQ reads that every 15 minutes as well: an application marked with a gold lightning bolt ⚡ is Preliminary: it was filed during the day and picked up live, and the FCC has not yet verified it. The FCC verifies new applications in its batch processing each night, Monday through Friday, when they are officially accepted and the red-light review begins. The bolt comes off only when the FCC's own nightly file confirms the application; a bolt-marked entry the FCC never confirms (withdrawn or deleted before processing) is removed.
• ●How does the FCC actually decide who gets a call-sign?
  Applications are held about 18 days after their receipt date. On the processing day, all applications with the same receipt date are put in a random order and processed one at a time. Each application is walked down its list of requested call-signs (up to 25, in the applicant's order of preference) and gets the first one that is still available. So whether you get your first choice depends on the random shuffle and on what earlier applications took. Applications from an earlier receipt date are always processed first.
• ●What does the 2-year rule mean?
  When a license expires or is canceled, the call-sign is not available to anyone else for two years, counted from the earlier of the expiration or cancellation date. "Too Early" outcomes show the date the call-sign opens; an application received before that date is dismissed even if the date passes while it is pending. The FCC does allow the former holder, and a close relative of a deceased holder, to apply sooner, but the public data does not say whether an applicant qualifies, so this page does not predict those exceptions: every application inside the 2-year window is shown as Too Early. If the FCC grants one anyway, the call-sign simply leaves this page (use Call-Sign Lookup to check its status).
• ●Which call-signs can I apply for?
  It depends on your license level. Amateur Extra: any format, including 1×2 (K5AB), 2×1 (AA5B, K5AB style with two-letter prefix) and 2×2 with an A prefix (AA5AB). Advanced: 2×2 with a K, N or W prefix, plus anything General can hold. General and Technician: 1×3 (K5ABC) and 2×3 (KA5ABC). Call-signs with KL/NL/WL/AL (Alaska), KH/NH/WH/AH (Hawaii and the Pacific) or KP/NP/WP (Puerto Rico and the Virgin Islands) prefixes require a mailing address in that region, whatever your level. Requests outside your level show "Insufficient Class"; wrong-region requests show "Restricted Region".
• ●What if two people apply for the same call-sign on the same day?
  That's "Competition". The random shuffle decides. This page simulates the FCC's processing many thousands of times (the count and accuracy are shown under the table) and reports each applicant's percentage chance. Two applicants with the call-sign at the top of their lists split it 50/50; a lower preference has a smaller chance because the applicant may already have received an earlier choice. Hover a call-sign, or open it, to see the chance. The percentage changes only when something real changes: a new application for the call-sign, a competitor paying or withdrawing, a call-sign being granted, or the license data updating.
• ●Why is my application marked "Possible Duplicate"?
  FCC rule 97.19(d)(1): if one applicant files more than one vanity application with the same receipt date, only the first one entered is processed. The others are dismissed. If you have duplicates pending, consider withdrawing the extras. The FCC is not always consistent about which one it keeps. Amending an application does not make it a duplicate: an amended application takes the date the FCC receives the amendment, and is not counted here even if several of your applications were amended on the same day.
• ●Why "Manually filed"?
  Since June 29, 2021 the FCC no longer accepts applications by mail or fax. Anything filed that way is dismissed.
• ●What if the applicant's license isn't in the data yet?
  It makes no difference to the prediction. The applicant's license class and mailing state are read from the FCC's own application record, so a brand-new licensee, or one whose license already sits under another call-sign, is judged like anyone else and holds his place in line.
• ●Why "Blocked by FCC pending renewal"?
  The requested call-sign has expired, but a pending renewal application is in process. Until the FCC acts on that renewal the call-sign is not available for assignment. Pending license renewals are the most common reason for a "Blocked by FCC pending renewal" label. Far less common reasons do occur and are handled by the FCC on a case by case basis.
• ●Why "Awaiting payment"?
  The FCC does not process a vanity application until its fee is paid, and dismisses it at processing if it is still unpaid. Until the FCC's ULS history shows a "Payment Confirmed" event, every call-sign on the application shows Awaiting payment (yellow) and the application is not counted as a competitor for anyone else. The moment payment is confirmed, the page recomputes and the application joins the race. Call-signs on the list that the applicant could never be assigned (wrong license level, wrong region, too early, reserved) keep that reason instead, because paying would not change it.
• ●Why "Offlined by FCC"?
  The FCC has set the application aside for manual review (an "offline" event in its history). It will not be processed on the normal schedule until the review clears, so no prediction is made and it is not counted as a competitor.
• ●What does "Unneeded" or "Higher Preference" mean?
  The simulation expects a call-sign earlier on the same list to be granted, so this one is never reached. It is neither a win nor a loss for that call-sign: if the earlier choice falls through (for example a competitor wins it), the lower preferences come into play and the page updates.
• ●Why "Withheld by FCC"?
  A few call-signs look available but are quietly withheld by the FCC. A 2024 Freedom of Information Act request found they were restricted as resembling obscenities. Only a couple are known (N6ER, N1GI); the full list has never been published.
• ●What do the colored file numbers and call-signs mean?
  The color summarizes the whole application or call-sign: green, a call-sign on the list is a certain assignment; gold, a real chance but contested; yellow, something the applicant can still fix (unpaid fee, offlined); red, no request on the list can be assigned, or the call-sign cannot be assigned to anyone; gray, no pending applications or not enough data. Hover for the one-line summary; click for the detail.
• ●How current is this page?
  Application and license data can lag the FCC by one to three days depending on the day of the week, because the FCC builds its daily files overnight and skips weekends for some tables; the exact dates of the application and license data in use are shown under the table, together with the time the predictions were computed. Applications picked up live from ULS (⚡) are ahead of the FCC files. Some available call-signs show a "prior license ended" date from decades ago: that is the most recent record for the call-sign in the FCC's public license file. Anything here is a prediction, not a guarantee.
• ●Is any personal information shown?
  No. Only call-signs, license levels and states. Names and addresses, although published by the FCC, are never displayed on this page.

Source: FCC ULS public access files, applied to W5ZQ's database. Outcomes are predictions, not guarantees.