One per line, or a column copied from a spreadsheet. Commas and semicolons between numbers work too. Up to 5,000 numbers at a time.
Texting tools and phone systems usually ask for E.164. The others are for printing and reading.
Duplicates are matched on the digits, so (512) 555-0142 and 512.555.0142 count as one. E.164 has no room for an extension, so turn Keep extensions off before you import into a texting or phone system.
Your list
Paste your list above. Every number shows up here in the format you pick, with a plain reason for any that need a look.
Your list stays in your browser. Nothing is uploaded or saved. These checks look at the digits only, so they can’t tell whether a number is in service, or whether it’s a cell or a landline. That takes a carrier lookup.
Sending a text to the numbers on your list? Check it fits in one message with the SMS character counter.
Want every call answered instead? See how FrontDesk Talk works.
One list, one format
Phone numbers pile up in every format: (512) 555-0142 from a web form, 512.555.0142 from a business card, 15125550142 from an old export, and a few with extensions on the end. That is fine for reading, but texting tools, phone systems, and imports want one consistent format, and they can reject or skip the rows that don’t match.
This formatter takes a pasted list or spreadsheet column, checks each number against the rules for US and Canada numbers, and gives it back in the format you pick. Duplicates come out, problems get a plain reason, and you can copy the clean numbers or download everything as a CSV. Your list never leaves your browser.
How to use the phone number formatter
1
Paste your list
Copy a column from your spreadsheet or paste numbers one per line. Commas and semicolons between numbers work too.
2
Pick a format and options
Choose E.164 for texting tools and phone systems, or a format that reads well in print. Then choose how to handle duplicates and extensions.
3
Fix, then copy or download
Check the rows marked Needs a look and fix them at the source. Then copy the ready numbers or download the CSV.
What E.164 is
E.164 is the international standard for writing a phone number: a plus sign, the country code, then the number, with no spaces or punctuation. A US or Canada number becomes +1 followed by 10 digits, like +15125550142. Texting services and phone systems use it because it points to exactly one number anywhere in the world, with no guessing about country codes.
Why lists get messy
People type numbers the way they say them, so one list mixes brackets, dashes, dots, and spaces. Spreadsheet apps add their own damage. They can drop the + from +1 numbers, show long numbers in scientific notation like 5.12555E+09, and lose the last digits for good if the file is saved that way. Extensions typed after the number, like ext 12 or x12, trip up imports that expect digits only.
What the checks can and can’t tell you
Each number is checked against the rules for US and Canada numbers: 10 digits, an area code and exchange that don’t start with 0 or 1, no service code like 411 or 911 in their place, and not one of the 555-0100 to 555-0199 numbers set aside for movies and examples. Toll-free numbers get their own label. None of this tells you whether a number is in service, or whether it is a cell or a landline. That takes a carrier lookup.
Keep consent with the list
A clean list is not the same as permission. Only text people who gave you their number and expect to hear from you, keep a record of who said yes and when, and take people off as soon as they ask. Marketing texts have stricter rules than replies to a customer who contacted you first. This is general information, not legal advice, so check with a lawyer about your own list.
Or let FrontDesk Talk handle it
Stop copying numbers off voicemail
FrontDesk Talk answers every call on the first ring, 24/7, and sends you a Talk Note by text and email after each one, with the caller’s name, number, and what they needed. Small Talk is $99 a month with no contract.
Questions
What is E.164 format?
It is the international way to write a phone number: a plus sign, the country code, and the number, with nothing else. In E.164, (512) 555-0142 becomes +15125550142. Pick E.164 above to convert a whole list at once.
How do I format phone numbers in Excel or Google Sheets?
Set the column to plain text before you paste or type numbers into it: Format, Number, Plain text in Google Sheets, or Format Cells, Text in Excel. That keeps the + and stops scientific notation. To fix a list that is already there, copy the column, paste it here, and paste the formatted numbers back into a plain text column.
Why is a number flagged?
Each flagged row says why. The usual reasons are a missing area code, a digit too many or too few, an area code that starts with 0 or 1, a fictional 555-01 number, a number outside US and Canada, or a cell a spreadsheet turned into scientific notation. Toll-free numbers get their own label because they can only get texts if they are set up for texting.
Does this upload my list?
No. The checking and formatting happen in your browser. Nothing is uploaded, saved, or sent to us, and the CSV is made on your own computer.
Does it check whether a number is real?
No. It checks that the digits follow the rules for US and Canada numbers, which catches typos and spreadsheet damage. It can’t tell whether a number is connected, who it belongs to, or whether it is a cell or a landline. That needs a carrier lookup from a phone or texting provider.
What happens to extensions?
With Keep extensions on, an extension stays on the end, like +15125550142 ext. 12. E.164 has no place for an extension, so turn Keep extensions off before you import numbers into a texting tool or phone system.
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