Blog
Guides on checking, cleaning and understanding phone number lists, what each check tells you, and how to get more out of every list
GuidesHow to choose a WhatsApp number checker: 10 questions to ask before you payDuplicates, exact prices, your WhatsApp account, file retention and support: ten questions to compare number checkers before you pay 
WhatsAppWhatsApp Quick, Standard or Detailed check: which one should you pick?The three WhatsApp checks side by side: what each one does, what it costs, when to use it and how to combine them on big lists
FacebookFacebook and Instagram ads: check your customer list before you upload itWhy customer lists often match badly in Meta Ads Manager, and how to check which numbers are linked to Facebook and Instagram before you build an audience
iOSiMessage or SMS: how to find out which numbers use an iPhoneBlue or green bubble: how to check one number by hand, how to check a whole list, and why it helps to know who uses an iPhone
RCSRCS vs SMS: which numbers can receive RCS messages?What RCS is, how it differs from SMS for businesses, and how to find out which numbers in your list can receive RCS messages
ListsHow to clean a phone number list before a campaignTen steps from a messy export to a list that is ready to use, including the Excel settings that stop your numbers from breaking
GuidesHow to write phone numbers in international format (with examples for 20 countries)The three rules of international phone number format, a table for 20 countries, and the mistakes that make numbers fail
WhatsAppHow to check if a phone number is on WhatsApp (one number or a whole list)Two quick ways to check a single number by hand, how to check thousands at once, and how to prepare your list and read the results