Can an ads.txt generator prove that a seller is authorized?

No. It can validate record syntax, but it cannot confirm that an account belongs to you or that a reseller is permitted.

What is the difference between DIRECT and RESELLER?

DIRECT means you control the listed seller account and contract directly with the advertising system. RESELLER means another authorized entity controls that account.

Should the first field contain the website that hosts ads.txt?

Not necessarily. It should contain the canonical domain of the advertising system where buyers connect, as specified by that platform.

Can I paste a complete URL into the domain field?

No. Enter a bare domain without https://, a path, port, username, or password. The generator validates the domain rather than extracting it from a pasted URL.

Where should the completed ads.txt file be published?

Publish it as a publicly accessible plain-text file at /ads.txt on the root domain that owns the advertising inventory.

Ads.txt Generator Tips and Common Mistakes

The safest ads.txt generator practice is to copy each authorized seller from platform instructions, validate every field, remove duplicates, and publish the reviewed file at /ads.txt on the inventory's root domain.

An ads.txt file is an Authorized Digital Sellers declaration. It lists advertising systems, seller or publisher account IDs, and the relationship that applies to each record. The format is simple, but formatting accuracy and authorization are separate. A clean generator export can still be wrong if its ID, relationship, completeness, or ownership has not been checked against the platform that supplied it.

This guide focuses on ads.txt generator tips and common mistakes, especially issues that syntax validation cannot settle. Before entering account details, use the ads.txt generator safety checklist to review data handling and operational safeguards.

Know What Belongs in Each ads.txt Field

Each seller becomes one comma-separated line. The IAB Tech Lab's ads.txt 1.1 specification defines the record structure used here.

Position	Required	What to enter	Useful check
Advertising system domain	Yes	The canonical domain of the advertising system where buyers connect. It is not necessarily the website hosting ads.txt.	Use a bare host such as google.com, without a scheme, path, port, username, or password.
Seller or publisher account ID	Yes	The exact identifier assigned by that advertising system.	Copy it from the platform's account or setup instructions; do not invent or convert it.
Relationship	Yes	DIRECT or RESELLER, depending on which entity controls the listed seller account.	Base the choice on business control, not on the appearance of the account ID.
Certification authority ID	No	The exact optional identifier supplied for that seller record.	Leave it blank unless the advertising platform provides it.

The first field describes the advertising system, not necessarily the domain where you will host the file. The generator lowercases and validates a bare DNS-style host rather than silently extracting a host from a pasted URL. Enter only the domain instead of expecting a full web address to be repaired automatically.

The account identifier's format belongs to the platform. Google's published guidance uses a pub- prefix followed by account digits, while other exchanges use different identifiers. Copy the exact value rather than applying another platform's format or guessing a placeholder.

Treat the certification authority field as platform-specific. Leave it blank unless the advertising system gives the exact value for your seller record. Do not reuse Google's published example with another exchange.

Choose the Seller Relationship by Account Control

DIRECT and RESELLER describe who controls the account named in the record. They are not interchangeable labels.

Situation	Correct relationship	Reason
You control the listed seller account and have a direct business relationship with the advertising system.	DIRECT	The declaration identifies your directly controlled account.
Another entity controls the listed account and is authorized to resell the inventory.	RESELLER	The declaration identifies an account controlled by a reselling entity.

Selecting the wrong relationship can make a declaration inaccurate even when every character is formatted correctly. The generator cannot prove that a reseller is permitted or confirm that an account belongs to you. Those checks require current instructions and records from the relevant advertising platform.

For the formatting stage, the Ads Txt Generator accepts seller details you explicitly supply. It validates three required comma-free tokens plus an optional certification token, lowercases the domain, prevents exact duplicate formatted rows, ends the file with a newline, and supports up to 200 records. The finished text can be copied or downloaded without sending account details to the server. It does not sign into ad accounts, verify authorization, or discover every platform selling your inventory.

Build and Publish ads.txt From Verified Records

Collect the source records. Open each advertising platform's account area or official setup instructions. Copy the advertising system domain, publisher account ID, relationship, and optional authority ID for every authorized seller. Do not infer missing values.
Enter the bare advertising-system domain. Remove https://, paths, ports, usernames, and passwords. Allow the generator to lowercase and validate the host rather than entering a full website URL.
Enter the exact account identifier. Preserve the form provided by that platform, including any required prefix or punctuation. Do not convert one system's identifier into another system's format.
Choose the relationship from account control. Use DIRECT when you directly control the listed account. Use RESELLER when another authorized entity controls it and resells the inventory.
Add the authority identifier only when supplied. Copy the exact optional value from the platform instructions. Otherwise, leave the fourth field blank.
Add each seller and review the complete list. Remove obsolete entries and retain existing valid sellers when adding a partner. The tool blocks exact duplicate rows, but you must still review stale or similar declarations that use different values.
Copy or download the finished file. Preserve its newline-terminated plain-text format and keep a backup of the previous version. The generator supports up to 200 records, so a larger supplied list exceeds its stated limit.
Deploy and compare the public file. Publish it as /ads.txt on the root domain that owns the inventory. Open the public URL and compare every line with the verified account records. A copy under /files/ads.txt, inside an HTML page, or behind authentication is not the same crawler-visible root resource.

Fix Common ads.txt Generator Mistakes Before Publishing

Syntax checks can prevent malformed output, but they cannot establish that every declaration is current, complete, and authorized.

Mistake	Why it causes problems	Correction
Using your website domain as the advertising-system domain	The first field identifies where buyers connect, which may be an exchange or advertising platform rather than your inventory site.	Copy the canonical domain from the platform's instructions.
Pasting a full URL into the domain field	The generator validates a bare host and does not silently extract one from a URL.	Enter only the domain, without a scheme, path, port, or credentials.
Guessing or converting a publisher ID	A well-formatted ID can still fail to identify the intended seller account.	Copy the exact assigned identifier from the platform.
Choosing DIRECT or RESELLER by appearance	The relationship may not describe who actually controls the account.	Verify the business relationship and account controller first.
Reusing a certification authority ID across exchanges	An identifier associated with one advertising system may not apply to another.	Use the exact value for the seller record or leave the field blank.
Replacing all existing sellers when adding one partner	The resulting file can become incomplete.	Retain existing valid sellers and add one verified record for each new account.
Leaving obsolete seller records in place	Account ownership, network relationships, and authorizations can change.	Compare the list with current partner records and remove stale entries.
Relying on syntax validation as proof of authorization	A syntactically valid but unauthorized or incomplete file can still harm monetization.	Verify every line against account-level source instructions.
Publishing at a nested path or behind a login	Buyers and crawlers expect the public root resource named ads.txt.	Place the plain-text file at /ads.txt on the inventory's root domain.

Verify the Public File Before Calling It Done

A valid download does not prove that deployment was correct. Perform a final comparison across the source instructions, generated text, and public response.

Confirm that every authorized advertising system and account is represented.
Check that each line contains the domain, account ID, and relationship in the correct order.
Confirm that every ID exactly matches the identifier supplied by its platform.
Verify that each DIRECT or RESELLER value reflects actual account control.
Look for exact duplicate output lines and manually review similar records with different values.
Remove obsolete entries while preserving other currently valid sellers.
Confirm that the downloaded file still ends with a newline after copying or deployment.
Open the public URL and ensure it returns the plain-text file at /ads.txt, not an HTML page or authentication prompt.
Compare every visible public line with the verified account records.

Keep the prior file as a backup and compare the change before replacing it. Account or network changes may require future updates, so review records whenever a partner changes its account ID, control relationship, or authorization. The generator cannot discover every platform that sells your inventory; current platform instructions remain the source for completeness and permission.