Evidence types and weights
Each piece of evidence carries a weight. Stronger, more direct evidence counts for more; expired certificates and conflicting reports apply penalties.
| Evidence | Weight |
|---|---|
| Direct phone call with restaurant staff | 1.00 |
| In-person visit | 1.00 |
| Recognized certificate on file (verified, not expired) | 0.95 |
| Owner/manager verification form | 0.75 |
| Invited trusted contributor | 0.60 |
| Approved community correction | 0.35 |
| Public discovery data | 0.20 |
| Anonymous community report | 0.10 |
| Expired certificate (penalty) | -0.30 |
| Conflicting reports (penalty) | -0.25 |
Halal tiers
Every listing is assigned one of the following tiers, with the public wording shown:
- certified
- Certified halal evidence available
- owner verified
- Owner or manager verified halal status
- community reported
- Community reported — not independently verified
- unverified
- Unverified listing
- not halal
- Reported not halal
- unknown
- Halal status unknown
Recognized certifying bodies
A certificate counts as certified-tier evidence only if it comes from a recognized body, is verified, and is not expired.
- ISWA — Islamic Society of Greater Houston
- IFANCA — Islamic Food and Nutrition Council of America
- HFSAA — Halal Food Standards Alliance of America
- HMA — Halal Monitoring Authority
- MCG — Muslim Consumer Group
- ISNA Halal — Islamic Society of North America — Halal
How the confidence score is calculated
The confidence score (0–100) combines a base evidence score, a structured-data score (whether the listing has a name, location, phone, hours, cuisine, neighborhood, and image), a freshness bonus for recent verification, and risk penalties (for example, an expired certificate, conflicting reports, or serving alcohol). The result is clamped to 0–100 and shown as a labeled band:
| Score | Band |
|---|---|
| 80–100 | High confidence |
| 60–79 | Medium confidence |
| 40–59 | Limited confidence |
| 20–39 | Low confidence |
| 0–19 | Insufficient evidence |
The score reflects evidence strength and freshness — not religious certainty.
Staleness and freshness
Information ages. We display a last-verified date on every listing and escalate the warning as time passes:
- 0–90 days
- Shown as “Verified [Month Year]” — no warning.
- 91–180 days
- Shown as “Last verified [Month Year]”.
- 181–365 days
- Amber warning: verified over 6 months ago — confirm before visiting.
- Over 365 days
- Red warning: data may be outdated — please verify directly.
- Never independently verified
- Shown as “Not independently verified”.