Realcaller gives every number a score from 0 to 1, built from how many reports it has, how much we trust the source, how recent the reports are and whether the number’s home country matches yours. Then it shows you the reason in plain words. Today the data is US government complaints; for Mexico, Realcaller can only learn from reports from its own users, and there are none yet. The app is still in development and is not on Google Play.
What does the score decide?
The score sets which card you see on a screened call:
| Score | Label on the card | Meaning |
|---|---|---|
| 0.70 or higher | Known spam | The number looks like spam |
| 0.40 up to 0.70 | Suspicious | Some reports, so be careful |
| Below 0.40 | Unknown caller, low risk | Not flagged as spam or suspicious |
The card is a phone notification. Its color is the same brand blue every time, so the verdict is in the words, not in a color you could misread. The body of the card shows the first reason. Calls the app checks get a card; calls from your saved contacts are skipped if you allow contacts access.
Which reasons can the card show?
A number gets at most three reason lines, strongest first. Examples, in the app’s wording:
| Reason line | When it appears |
|---|---|
| Flagged by FTC (or Flagged by FCC) | The number comes from that agency’s complaint data |
| Reported {n} times, most recently in the last 30 days | Complaint count from a data source, with a recent complaint |
| Reported by {n} Realcaller users in the last 30 days | Users of the app reported it |
| Recent activity spike: {n} reports in 24h | At least 5 user reports in 24 hours |
| Source data is from {country}; your region is {country} | A live lookup found a number whose data is from another country than your SIM’s |
| New number: no reports yet | Nothing is known about it |
In these lines, {n} and {country} stand for the real values the app fills in.
How is the score built?
The formula is fixed and any change to it needs a special review. In plain words:
- 50% report volume. The weighted count of reports, which maxes out at 50. Each FTC or FCC complaint counts as 1. Each Realcaller report counts for as much as its reporter’s trust weight. Counts fade by 1% every night.
- 20% source trust. FTC data counts for 1.0, FCC data for 0.9, and numbers known only from user reports start at 0.4.
- 20% freshness. It drops to about a third 30 days after the last report, keeps fading after that, and never goes below 0.05.
- 10% region match. Full credit when the number’s source country matches your SIM’s country, and 30% of it when it does not.
The result is kept between 0 and 1.
Where does the data come from?
| Source | Region | What it is |
|---|---|---|
| FTC | United States | Do-Not-Call complaint files, public domain |
| FCC | United States | Consumer complaints in the “Unwanted Calls” category, public domain |
| Realcaller users | Anywhere | Spam reports sent through the app |
As of 2026-10-07 the database held 813,371 numbers, all US, from the FTC and the FCC. There were zero user reports in production on that date. Those two figures change over time: the government data is refreshed every Monday.
What about Mexico?
There is no Mexican data in Realcaller today. We did not find a Mexican source with phone numbers we could use, so coverage in Mexico can only come from reports by app users. A phone with a Mexican SIM can still look up any number and gets the top US numbers in its offline list, but a Mexican scam number with no reports will read “New number: no reports yet”. We say this plainly because it affects what you can expect.
How much does one report count?
Not much, on purpose. A new phone’s reports weigh 0.3. A phone that has reported at least 5 numbers that went on to reach Known spam rises to 0.6. Weights stay between 0.1 and 1.0. In numbers: one report from a new phone on an unknown number gives a score of about 0.38 on a live lookup, which is still “low risk”. For a number known only from user reports, reaching Suspicious takes roughly 7 reports from new phones while the reports are fresh.
Other rules protect the data. The same phone cannot report the same number twice in 24 hours, a phone can send 10 reports a day, and a burst of more than 50 phones reporting one number within an hour goes to a manual review with no automatic score change.
Why do reports take two steps?
A report cannot be sent with one tap. First you pick a category: Robocall, Telemarketer, Scam, Phishing, or Other with a description. Then you confirm a message like “Submit report for ***NNNN as Scam?” with Cancel and Submit. Two deliberate steps keep casual mistakes out of the data. The number is shown as only its last four digits in that message.
Will the app block calls for me?
Not unless you turn it on. Automatic blocking is off by default. You can choose to block known spam, or known spam and suspicious calls.
Everything here comes from Realcaller’s own documentation of the app as of 2026-10-07. Figures from that date will change.
