NoCall

Transparency

At NoCall we believe trust is built with transparency. Here we explain how our system works, how we calculate risk score, where our data comes from, and how we protect your privacy.

How our reporting system works

NoCall is a community platform: users identify and report spam numbers. The process works like this:

  1. A user reports a number — From the website, without an account, or from the app, signed in, anyone can report a suspicious number and choose its category (telemarketing, scam, debt collection, surveys, harassment, etc.).
  2. An admin reviews every report — Reports and comments sent through NoCall stay pending until an admin approves or rejects them. There is no automatic filter for offensive words or personal data.
  3. Approved reports enter the spam database — When a report is approved, the number joins the block list that syncs to the NoCall app.

Number pages also show comments that do not come from NoCall users: text taken from other websites and automatically generated text. Those comments do not go through this review and are shown with their origin stated.

Risk score

Every number in our database has a risk score from 0 to 100. It is calculated automatically with the following formula:

risk = min(100, reports × 5 + (verified ? 30 : 0) + min(10, external opinions × 2))

Each approved report adds 5 points, and verification by our team adds 30 more. Public opinions collected from other websites add at most 10 points.

Risk levels are classified as follows:

Low0–39

Few or no reports. The number shows no clear spam signals.

Medium40–59

Several reports received. Exercise caution before answering.

High60–79

Many confirmed reports. High likelihood of spam or aggressive telemarketing.

Critical80–100

Number verified as spam or scam. Blocking immediately is recommended.

Operator data

For each number you look up, NoCall automatically identifies the telecom operator and line type (mobile, landline, special rate, etc.). This information comes from public data of the NCC (Nigerian Communications Commission), the regulator for telecommunications in Nigeria.

NCC data includes numbering block assignments for each operator, which lets us determine precisely which company owns a number and whether it is mobile, landline, or special rate.

Privacy and data

Privacy is a top priority at NoCall. Our commitments:

  • Minimal data — To report from the website you need no account and do not give your name or email. If you sign in to the app, we store your account's email and name to manage the account.
  • Report limit — To limit abuse we store the IP address and the device identifier with each report, and the account if you are signed in. One report per number is accepted every 7 days from the same device, IP or account. Reports are published without your name.
  • Cookies only with your consent — Without your consent we only use the cookies the site needs to work. If you accept them in the cookie notice, we turn on analytics (Google Analytics, PostHog and Microsoft Clarity) and Google AdSense ads. You can change your choice at any time.
  • GDPR compliance — NoCall complies with the EU General Data Protection Regulation.
  • On-device processing — In the app, call and SMS filtering runs on your device without sending that data to external servers.

Open database

NoCall’s database is built by the community and helps protect everyone. Each report improves detection of spam and phone scams in Nigeria.

79
Spam numbers detected
2
Community reports

Anyone can look up a number on our website to check whether it has been reported, read the published comments and see its risk level, without signing up. Each comment shows whether it comes from a NoCall user and was approved by an admin, or comes from another source.

Code of conduct

To keep our database accurate and trustworthy, we apply these rules:

  • False reports are not allowed — Deliberately reporting a legitimate number as spam violates our rules.
  • Manual moderation — Reports and comments sent through NoCall are reviewed before they are published. In the app, a single flag from a user takes a published comment down and sends it back to the review queue.
  • Review requests — If a number was reported by mistake, its owner can ask for a review by email, from the contact page or from the form on the “My number shows as spam” page. There is no fixed response time.
  • Continuous improvement — We use community feedback to improve detection algorithms and moderation processes.
About NoCallFAQContact