How SpinCounts Works

Where the data comes from

SpinCounts monitors the live "now playing" and play-history feeds that radio stations broadcast alongside their streams, around the clock. The network — currently 6,700+ active stations, with a U.S. focus — spans three kinds of radio:

• Terrestrial FM streaming online, including iHeartRadio market stations;
• SiriusXM satellite channels; and
• Internet broadcasters streaming across the major online radio platforms and directories.

Each play is captured with the station, the exact air time reported by the station's feed, and the station's location. The full roster is public — browse the station directory to see every station and its logged play history. Stations join the network continuously; broadcasters can claim or submit a station free.

How plays get matched to songs

A raw feed entry ("ARTIST - Title") becomes a verified spin through matching: titles and artist names are normalized and matched against our catalog, then enriched with release metadata from major music catalogs — including the recording's ISRC (International Standard Recording Code), album, label, genre and artwork. ISRC anchoring ties airplay to the specific recording rather than a loose text match, which matters when different songs share a title.

Matching is never perfect at radio scale, so it's backed by ongoing curation: station-break and advertising strings are filtered out before they count, junk data is purged when a station's feed misbehaves, duplicate artist and track records get merged, and mismatches reported to us are fixed by hand. Pages without any recorded airplay are excluded from search-engine indexing until they earn data.

How fresh the numbers are

Spins: posting time depends on how each station publishes its play history — minutes for some stations, a few hours for many. We measured it: across 1,465,990 plays logged from 3,673 stations over 48 hours in September 2026, 11% were stored within 5 minutes of airing, 22% within 15 minutes, 46% within an hour, 65% within two hours and 99% within four. SiriusXM channels were the fastest (99% within 15 minutes). These figures describe the plays we logged — a station that only exposes its last few songs can have gaps between our reads. Every spin keeps the air time the station reported, regardless of when it posts. See our measured detection times.

Totals: a track's lifetime count combines its permanent play ledger with the most recent weeks of live spins — what you see on a page is the full recorded history, not a rolling window.

Charts: airplay charts rank songs released in the last 24 months purely by verified spins in each chart's window. Older catalog songs keep their pages, play counts and reports but do not take chart positions, so the charts reflect current music; a song whose release date we do not know yet is ranked. So that one station cannot carry a song, each station counts at most 50 plays of a song per chart week; track pages and play counts still show every play. The chart week runs Saturday to Saturday, publishes Sundays at 6 PM ET, and movement arrows compare against the previous week's frozen snapshot; from a song's second week each position also shows its peak and weeks on the chart (counted since October 2026). Chart positions cannot be bought: there are no submissions, votes, or pay-for-placement. (Paid Airplay Campaigns promote a track to stations and on-site placements, clearly labeled — they never alter chart math, which counts real spins only.)

Estimated Audience

Where we know a station's city and time zone, each logged play carries an Estimated Audience: a modeled estimate of potential radio exposure for that one play. It is worked out from four things: the population of the station's city, the share of that population assumed to be listening to radio, the station's assumed share of that local radio audience, and a time-of-day factor for when the play aired.

Time of day follows the station's own local clock, with daylight saving applied, and is grouped into five parts of the day: morning drive, midday, afternoon drive, evening and overnight. The two drive times carry the most listening, midday a normal amount, the evening less, and overnight the least.

An estimate is calculated when the play is logged and stored with it. If we later refine our assumptions, new plays use the new values and earlier plays are not rewritten. Where we do not have a station's location there is no estimate, and reports show a dash rather than a zero; when only some of a report's plays have an estimate, the report says how many. A station whose estimate for each play is too small to show also gets a dash, with a note saying so. Satellite channels have no home city, so they use the service's subscriber base in place of a city population.

Estimates added together are called Estimated Audience Impressions. They are never used in our charts, which rank songs by verified spins only.

A step-by-step explanation with a worked example: How SpinCounts estimates audience, and how to read the number.

Estimated Audience is a modeled estimate of potential radio exposure based on population, radio listening assumptions, station share, and time of day. It does not represent verified or unique listener counts. Estimated Audience Impressions may include repeat exposure to the same listener.

City population and time-zone data © GeoNames (geonames.org), licensed under CC BY 4.0.

What we don't claim

• No service monitors every station on earth — including this one. Treat any spin count, here or anywhere, as "at least this many within the monitored network." Coverage is strongest for U.S. FM streams, SiriusXM and internet radio.
• SpinCounts is not a royalty census. Performance royalties are paid by PROs (ASCAP, BMI, SESAC) and SoundExchange from their own licensed data. Our logs are an independent record you can cross-reference — see airplay reports — not a payment system.
• We are independent. SpinCounts is not affiliated with Billboard, Mediabase, Nielsen, or any PRO. Comparisons we publish about other services are date-stamped and drawn from those services' own public materials.

Corrections

If a spin, match, or artist attribution looks wrong — a play credited to the wrong recording, a junk title that slipped through, a duplicate profile — tell us. Reported issues are investigated against the raw feed logs; confirmed errors are corrected by fixing the match, merging duplicates, or purging bad data, and the fix propagates to every page, chart and report built from it. Artists can also flag issues directly from their claimed artist page.

Want the product view of all this — search, maps, charts and reports in one place? See how the SpinCounts radio airplay tracker works, or start with the artist directory.