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Known Traveler Number Validator

Finance & Global IDs

Validate a TSA PreCheck Known Traveler Number (KTN) or Global Entry PASSID format instantly. Checks the 9-digit structure. Free, client-side, no data stored.

Reviewed by the thecalcu.com team · Last updated July 25, 2026

What is a KTN?

A Known Traveler Number (KTN) validator checks whether a given KTN matches the expected format for US Trusted Traveler Programs, specifically the 9-digit numeric format used by TSA PreCheck, Global Entry, NEXUS, and SENTRI. The KTN, also called a PASSID for Global Entry members, is the identifier entered in airline booking profiles and reservation forms to receive TSA PreCheck on your boarding pass.

The KTN system was established to allow low-risk, pre-vetted travellers to pass through airport security without removing shoes, laptops, and liquids, and without going through full-body scanners. Millions of US travellers are enrolled in these programmes, and correctly entering the 9-digit KTN in their airline profile is the key step that makes the PreCheck indicator appear on the boarding pass. A single transposed digit means no PreCheck, a common and frustrating outcome that this validator helps prevent.

The standard format for all current Trusted Traveler programme identifiers is a 9-digit number: no letters, no hyphens, no spaces. The validator confirms this structure and also accepts alphanumeric identifiers in the 8–12 character range for older NEXUS or SENTRI formats that may predate the current 9-digit standard. Use it alongside the US Passport Validator when verifying travel document details before an international trip.

Why Use a Known Traveler Number Validator?

A mistyped KTN in an airline profile causes the PreCheck indicator to be missing on every future booking until the error is caught and corrected. Since airlines typically pull KTN data from the traveller profile at the time of booking, not at check-in, the error may go unnoticed until the traveller arrives at a standard security line. Validating the format before entering it in an airline profile catches the most obvious errors: wrong length, accidental letters, missing digits.

Who Should Use This Validator?

Frequent flyers who are new to TSA PreCheck or Global Entry and are entering their KTN in multiple airline profiles for the first time can confirm the format is correct before saving it.

Corporate travel managers who maintain employee travel profiles for a company often input KTNs provided by employees. A quick format check confirms the number has not been transcribed incorrectly from the employee's enrolment confirmation.

Travel agencies booking business travel can validate KTNs provided by clients before adding them to passenger name records (PNR).

Developers building travel booking platforms that collect KTNs as part of the traveller profile can use the validator logic as a client-side input check.

What Insights Does the Known Traveler Number Validator Give You?

A valid result confirms the KTN is 9 digits (or a plausible alphanumeric format for legacy programmes) and notes that the format matches the TSA PreCheck / Global Entry PASSID standard. An invalid result gives the length of what was entered and notes the discrepancy, helping you identify whether a digit is missing, extra, or replaced with a letter.

The validator also notes in the result that this is a format check only, confirming you need to verify active enrolment through the CBP TTP portal if you have questions about membership status.

How to use this KTN calculator

  1. Find your KTN in your TSA PreCheck enrolment confirmation email, your CBP TTP account (ttp.cbp.dhs.gov), or the airline loyalty profile where you previously saved it.
  2. Enter the number in the Known Traveler Number (KTN) field.
  3. The result shows immediately: Valid for a correctly formatted 9-digit number, or Invalid with the specific issue.
  4. If valid, enter the exact same number in your airline profile under the "Known Traveler Number" or "TSA PreCheck" field.
  5. Book a flight and confirm the TSA PreCheck indicator (TSA PRE✓) appears on your boarding pass.
Show formula & methodology ↓Show less ↑

Formula & Methodology

The validator applies two pattern tests:

Primary check (standard TSA PreCheck / Global Entry PASSID):
/^\d{9}$/
Exactly 9 digits, no letters, hyphens, or spaces.

Secondary check (legacy alphanumeric formats):
/^[A-Z0-9]{8,12}$/i
8–12 alphanumeric characters, for older NEXUS and SENTRI identifiers.

If the primary check passes, the result is confirmed as a standard TSA PreCheck / Global Entry format. If only the secondary check passes, the result notes it may be a legacy or alternative programme format.

Valid examples:
- 123456789, standard 9-digit KTN
- 987654321, standard 9-digit KTN

Invalid examples:
- 12345678, 8 digits (one short)
- 1234567890, 10 digits (one too many)
- ABC123456, contains letters (not valid for current standard)

Related Tools

You may also find these useful: NPI Number Validator, CUSIP / ISIN Validator.

Frequently Asked Questions

What is a Known Traveler Number (KTN)?
A Known Traveler Number (KTN) is the identifier assigned to members of US Trusted Traveler Programs such as TSA PreCheck, Global Entry, NEXUS, and SENTRI. It is also called a PASSID for Global Entry, NEXUS, and SENTRI members. The KTN is entered when booking flights so the TSA PreCheck indicator appears on your boarding pass.
What format does a KTN follow?
TSA PreCheck KTNs are 9-digit numbers. Global Entry, NEXUS, and SENTRI PASSIDs are also 9-digit numbers assigned by CBP (Customs and Border Protection). Some programme numbers may be alphanumeric in older formats, but the current standard for all US Trusted Traveler Programs is a 9-digit numeric identifier.
What does this Known Traveler Number validator check?
The validator checks that the KTN is 9 digits (the standard format for TSA PreCheck and Global Entry). It also accepts alphanumeric identifiers of 8–12 characters as possible NEXUS or SENTRI numbers. It is a format check only, it does not confirm enrolment status or programme membership with TSA or CBP.
Where do I find my KTN?
Log in to the CBP Trusted Traveler Programs website at ttp.cbp.dhs.gov to find your PASSID/KTN. For TSA PreCheck members enrolled through a third-party TSA PreCheck provider, the KTN was provided in your enrolment confirmation email or letter. It is also shown in the TSA PreCheck enrolment portal.
Does a valid KTN format mean I am enrolled in TSA PreCheck?
No. This tool validates only the format of the number, that it matches the expected length and character pattern. It cannot confirm that the number is active, that your programme membership has not expired, or that the number is correctly linked to your name in TSA or CBP systems.
Why is my TSA PreCheck indicator not showing on my boarding pass?
Common reasons include: the KTN was entered incorrectly in your airline profile, the KTN is not linked to the name on your ticket, your membership has expired, or the airline has not processed the TSA PreCheck data for that flight. Validate your KTN format here and confirm it matches your enrolment confirmation exactly before updating your airline profile.
Is my KTN the same as my Global Entry card number?
Not exactly. Your PASSID is the 9-digit number in the CBP system and is what you enter in the KTN field when booking. Your Global Entry card may have a different identifier printed on it. Always use your PASSID from the TTP website, not the number printed on the physical card.
Can I share my KTN with someone else to use TSA PreCheck?
No. A KTN is tied to your specific identity in TSA and CBP systems. Using someone else's KTN in your booking is ineffective (it will not apply PreCheck to your boarding pass) and potentially fraudulent. Each TSA PreCheck member needs their own enrolment and KTN.
Is my KTN stored or uploaded when I validate it here?
No. Validation runs entirely in your browser. Your KTN is never transmitted to a server or stored anywhere. Trusted Traveler Numbers are considered sensitive identification data and you should not share them with untrusted third parties.
How long is a TSA PreCheck membership valid?
TSA PreCheck membership is valid for five years. Your KTN remains the same throughout this period. You must renew before expiry to continue receiving PreCheck benefits. Renewal can be done online through the TSA PreCheck or CBP TTP website.
What is the difference between TSA PreCheck and Global Entry?
TSA PreCheck provides expedited security screening at US domestic airports. Global Entry provides expedited US Customs processing for international arrivals at major US airports and automatically includes TSA PreCheck. Global Entry requires an in-person interview and a background check, making the enrolment process more involved.
Also known as
KTN validatorTSA PreCheck numberGlobal Entry PASSIDknown traveler number checkTSA trusted traveler