VAT number format checkerValidators

VAT number validator. Format and check digits.

Paste one or many VAT numbers and see the country, whether the format is right and whether the check digits match. It does not call the EU VIES register, so it cannot tell you a number is registered.

Cost to you

Free

Runs in your browser. No signup, no API call, no limit per hour.

browser
runs in
none
API calls
none
account

Use it now

Use the VAT number format checker here

It runs in your browser. Nothing you type is sent anywhere, there is no signup and no limit.

Loading the tool.

Run it from your agent

Copy one prompt, give it to your agent.

Fill in the placeholder, paste it, and the agent runs the same job with current data on your looot account and shows the cost.

  • You give it: vat numbers with their country prefix.
  • Billed per call, nothing while your agent is idle.
  • The agent shows the price before it calls.
Prompt: VAT number format checker
Use looot to check these VAT numbers before I invoice: [paste numbers, one per line]. 1. Set up https://looot.ai/skill.md. 2. Clean each number: upper case, no spaces or dots, GR becomes EL. 3. Check each against its country's format and check digit rule and flag the ones that fail. 4. Return a table of number, country and verdict, and say which ones still need a register check.

Give this to your agent
Setup command
set up looot - https://looot.ai/skill.md

What comes back

What your agent gets from vat number validator

Field names as the providers return them. The exact set varies by endpoint, and your agent reads it from the catalog.

  • country of the number
  • format valid or not
  • check digit result for the countries that have one
  • what a valid number looks like for that country

Use it for

What people do with vat number validator

  • Before you invoice

    Catch a typo in a customer's VAT number before it goes on an invoice.

  • Clean a customer list

    Paste a column of numbers and see which ones fail the format or the check digits.

  • Spot the country

    See which country a number belongs to from its prefix.

  • Check sign-up forms

    Use the same rules to stop a mistyped number at the form.

Set up once

Three steps. Your agent does the rest.

Keep going

More free tools

FAQ

Questions about vat number validator

Paste it with its two letter prefix, such as DE136695976, in the box at the top of this page. You see the country, whether the format is right and whether the check digits match.

No. It checks the format and the check digits in your browser. A number can pass here and still not be registered or active. Use the official VIES site of the European Commission to confirm registration.

All 27 EU countries plus GB for the United Kingdom and XI for Northern Ireland. Check digits are tested for 20 of them. For the others only the format is checked, and the result says so.

Greek VAT numbers use the prefix EL. The checker reads GR as EL, so both work.

The number has the right length and shape, but its last digits do not match the rest. That almost always means a typo. Ask the customer for the number again.

Yes. Switch to the list mode and paste one number per line. Download the results as CSV.

Yes. It runs in your browser with no account and no limit. Nothing you type is sent anywhere.
For agents
tool
VAT number format checker
category
Validators
input
VAT numbers with their country prefix
output
country of the number, format valid or not, check digit result for the countries that have one, what a valid number looks like for that country
price
per call, read live from the catalog on the web page
web tool
runs in the visitor's browser, no API call, free and unlimited
schedule
on demand
setup
https://looot.ai/skill.md
llms.txt
https://looot.ai/llms.txt
updated
2026-10-14
markdown /free-tools/vat-number-validator.md

Run vat number validator from your own agent.

Start your workspace, top up, and paste the prompt into the agent you already use. It runs the job with live data and shows the cost first.

Start your workspace See all free tools