Know which numbers are real before you dial.
Phone number validation for B2B and B2C contact lists. Check one number, a pasted list, or an entire CSV against live carrier data, and export clean results in minutes.
- No credit card required
- Free validations to start
- CSV export included
- Live carrier lookups
- Encrypted in transit
- Payments by Square
- Export results anytime
Features
Every way you need to validate, in one place
Pick the method that fits the job. Results look the same whichever way you check, and every run is saved.
contacts-q3.csv
2.4 MB
Upload a CSV
Validate up to 10,000 rows at once. We detect the phone column, remove duplicates and skip empty rows for you.
(415) 555-2671 · US
Single number
Check one number in seconds before you call, text, or save it to your CRM.
+14155552671
+442071838750
(212) 555-0147
+61293744000
Paste a list
Drop in up to 1,000 numbers, one per line, in any common format.
History and downloads
Every run is saved to your history with its counts. Download the full results as a CSV whenever you need them.
B2B and B2C lists
Tag every run as business or consumer so your lists stay organised.
Duplicates removed
Repeated numbers and rows without a phone number are skipped automatically.
International formats
Numbers with a country code, plus 10-digit US and Canadian numbers in any style.
Honest results
Valid, invalid, or not checked. We never guess when a lookup could not complete.
How it works
From raw list to clean data in three steps
- 01
Create an account
Sign up with your email in under a minute. No card required to start.
- 02
Add your numbers
Type a single number, paste a list, or upload a CSV exported from your CRM.
- 03
Export clean data
Review valid, invalid and unchecked numbers, then download the results as a CSV.
Who it's for
Built for teams that rely on reachable contacts
Bad numbers waste calls, campaign budget and time. Validate before you reach out, not after.
Sales teams
Spend dialing time on prospects you can actually reach.
Marketing
Clean SMS and call lists before every campaign goes out.
Recruiting
Confirm candidate contact details before you reach out.
Data operations
Keep CRM records accurate as lists grow and age.
Pricing
Simple, transparent pricing
Start for free. Upgrade when you need unlimited validation.
Free
For trying things out and occasional checks.
$0forever
Create free account- 5 free validations
- Single, list and CSV validation
- Downloadable results
Prices in USD. Payments are processed securely by Square.
FAQ
Frequently asked questions
Everything you need to know about validating numbers with Valid Number Check.
How are numbers validated?
Each number is checked against live carrier lookup data, so you know whether it is a real, assignable number rather than just correctly formatted.
What does “Not checked” mean?
It means the lookup could not be completed, for example because of a temporary provider issue. We report it separately instead of marking the number invalid.
What format should my CSV be in?
Any CSV with a header row. We read the column named phone, mobile or similar, and fall back to the first column. Files can be up to 10 MB.
Which number formats are supported?
International numbers with a country code, like +44 20 7946 0958, and 10-digit US and Canadian numbers in any common format.
Can I download my past results?
Yes. Every run is saved to your history, and you can download the full results as a CSV at any time.
Stop calling numbers that don’t exist.
Create an account and validate your first list in under a minute.