344 guides

Guides to verification and phone privacy

Short, practical answers: how verification works, what to do when a code doesn’t arrive, and how to keep your real number out of databases.

Getting started

Getting startedHow to receive SMS online without your own numberHow receiving SMS online works, free inbox sites vs private numbers, which countries work best, and how to get your first verification code in about a minute.Read the guide →
Getting startedVoIP vs mobile numbers: why apps reject someApps check what kind of number you enter. Here’s what they look for and why mobile numbers pass.Read the guide →
Getting startedHow to get a US phone number from another countryThe options for a +1 number when you don’t live in the US, what each costs, and which one fits a one-time code.Read the guide →
Getting startedHow to write an international phone number (and the 0 mistake)Country codes, the + sign and the leading 0: why apps call a correct number “invalid” and how to fix it.Read the guide →
Getting startedWhat is an OTP code? SMS OTP explained simplyOne-time passwords in plain English: what an OTP is, how SMS OTP works, why the code sometimes never arrives, and how to receive one without your own number.Read the guide →
Getting startedTemporary phone number for verification: how it worksWhat a temporary number is, how long it lasts, which apps accept one and what happens to the account when it closes.Read the guide →
Getting startedWhat is a non-VoIP phone number (and where to get one)Why apps ask for a “non-VoIP” number, how they tell the difference, and the ways to get one without a contract.Read the guide →
Getting startedFree phone number for verification: what actually worksThe free options, honestly ranked: what each one costs you in privacy, and when it’s worth paying a few cents instead.Read the guide →
Getting startedWhat is a virtual phone number?Virtual numbers explained in plain words: how they receive texts without a phone, the types that exist, and what each is good for.Read the guide →
Getting startedGoogle Voice alternatives for SMS verificationGoogle Voice is free but often refused for verification codes, and it needs a US number to start. These alternatives work differently.Read the guide →

Troubleshooting

Safety & privacy

App guides

App guidesHow to test your app’s SMS verification in other countriesFor developers and QA: check that codes arrive, sender names look right and limits behave, without a drawer of SIM cards.Read the guide →

Receive a code without a SIM card, app by app

320 apps: why each one asks for a phone, how to get the code online, and how to keep the account afterwards.