How the directory is built

The directory grades companies by the line type of a phone number, the same way the checker grades any number. Nothing on the board is an opinion about a company. Every grade is what Twilio Lookup returned for a specific number on a specific date.

What we check

• Published number. The phone number a company shows publicly, on its site, in its docs, or in a demo. We record the page it came from and link to it.
• What you get. Where we have signed up or bought a number ourselves, the number a real user is actually given. This is marked verified and it is the stronger evidence. Where we do not have it, the row rests on the published number alone.
• Allocation. Whether a user gets a dedicated line, shares one number with everyone, or the product runs on the user's own phone number. Marked unknown when we could not determine it.

How a number is graded

Each number is run through Twilio Lookup v2 with the line type intelligence field. The score is set by line type alone: mobile 95, fixedVoip 45, nonFixedVoip 15, voip 15, landline 10. Toll-free and unclassified numbers are not scored. A real carrier tops out at 95, never 100, because even a real number can be blocked if its range has a bad reputation. Grades: A 90 to 100, B 70 to 89, C 50 to 69, D 30 to 49, F 0 to 29.

Limits you should know

• A company's public demo number may differ from the number it provisions per user. That is why the board shows both where it can.
• Line type databases disagree with each other. Twilio is one widely used source, not the only one.
• Numbers change hands and carriers. Every row carries the date it was last checked (currently 2026-09-16).
• Full numbers are never published. Rows show a masked form and the source page.
• Gather, which builds numberRank, is listed and labeled as ours. It is graded by the same lookup as everyone else.

Corrections and right of reply

If you are listed and believe a row is wrong, the contact address in the footer once it is published with the company name, the number you believe should be tested, and where it is published. We will re-run the lookup, update the row, and record the change in the changelog. The same rules apply to every company, including Gather. We do not remove a company because it asks; we correct the data when the data is wrong.

Companies that appear with an F grade are told what number was tested, when, and how to contest it, before we promote the board more widely.

Adding a company

Send the public page where the number is published. If you can also share a number a real user was provisioned, the row gets a verified "what you get" line.