Normalize Phone Numbers in CSV & Excel

Convert phone numbers written in every possible way — 98765 43210, (415) 555-2671, 091-98765-43210, +44 (0)20 7946 0958 — into one international format. Choose the country your numbers are from; numbers that already include a + country code are recognised automatically.

Drop a CSV or Excel file here

.csv, .xlsx, .tsv

Your file stays on your device. It's read and cleaned in your browser — nothing is uploaded.

How it works

Step 1
Upload the file
CSV or Excel. Columns named phone, mobile, tel, WhatsApp and similar are recognised as phone columns.
Step 2
Set the country
Tell us which country numbers without a + country code belong to. It's shown in the report, never assumed silently.
Step 3
Convert & review
Numbers become E.164 (+country code + number). Invalid ones are listed so you can review, clear or keep them.

What it checks and fixes

Mixed formats

Spaces, dashes, dots, brackets, leading zeros (trunk prefixes) and country codes with or without + or 00.

Invalid numbers

Too short, too long or impossible for the selected country — reported with examples instead of silently changed.

Extensions

Numbers like 9876543210 x42 or “ext. 42” keep their extension.

International numbers

Numbers with a + or 00 prefix are matched to 44 supported countries; other valid-looking international numbers are formatted and marked unverified.

Why use E.164?

E.164 is the international standard for phone numbers: a + sign, the country calling code and the national number, with no spaces or punctuation — for example +919876543210 or +14155552671. It's the format most CRMs, SMS and WhatsApp platforms, dialers and marketing tools expect, and it's unambiguous: the same number can't be written two ways.

Input	Country setting	E.164 output
98765 43210	India	+919876543210
098765 43210	India	+919876543210
91-9876543210	India	+919876543210
(415) 555-2671	United States	+14155552671
020 7946 0958	United Kingdom	+442079460958
+971 50 123 4567	any	+971501234567

Why the country matters

A number like 9876543210 is a valid Indian mobile number and also a plausible US number. Without knowing the country, any tool that converts it is guessing. TheSpreadFix pre-fills the country from your browser's region, but always states it in the report (“Numbers without a country code are treated as India (+91)”) so you can change it before applying anything.

If your file mixes countries, numbers that already start with + or 00 are handled correctly whatever the setting; only national-format numbers use the selected country.

What “invalid” means here

Validation checks the length and prefix rules for the country — it tells you a number is badly formatted or impossible, not whether it's in service. Invalid numbers are kept unchanged by default; you can choose to clear them instead. Values that clearly aren't phone numbers (like “call me”) are always reported, never altered.

Frequently asked questions

Which countries are supported?

44 countries including India, the US, Canada, the UK, UAE, Saudi Arabia, Singapore, Australia and most of Europe. Numbers with other country codes are formatted and marked “unverified”.

Can I get the national format instead of E.164?

The cleaner converts to E.164, the most widely accepted format. Other formats (with a space after the country code, or national digits only) are supported by the engine and will be selectable in a future update.

What happens to invalid numbers?

They're left exactly as they were and listed in the report. You can choose to clear them instead.

Does it check if a number is active?

No — it's a format check. It can't tell whether a number is in service.

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