====== Frequently Asked Questions ======

===== General =====

=== Does NDC Lookup require an internet connection? ===

No. The complete FDA NDC database is bundled with the app. All searching, browsing, and barcode scanning works entirely offline.

=== How large is the app? ===

Approximately 250 MB, most of which is the bundled NDC database.

=== What devices does it run on? ===

iPhone, iPad, and Mac (via Mac Catalyst). Requires iOS/iPadOS 17.0+ or macOS 14.0+.

=== Is the barcode scanner available on Mac? ===

No. The barcode scanner uses the device camera and is only available on iPhone and iPad.

===== Database =====

=== Where does the NDC data come from? ===

The data comes from the FDA's National Drug Code Directory, a public database maintained by the U.S. Food and Drug Administration.

=== How current is the database? ===

The database version and last updated date are shown in **Settings**. The database is updated with each app release.

=== How many products are in the database? ===

The database contains approximately 140,000 products and 280,000 packages. The exact counts are displayed on the Search tab.

===== Search =====

=== Can I search by 11-digit NDC? ===

Yes. You can search by either 10-digit or 11-digit NDC, with or without hyphens.

=== Why do some drug names appear in different cases? ===

Brand names are displayed in Title Case and generic names in lowercase. This is a display convention — the underlying FDA data may have inconsistent casing.

=== What does "ID:12345" do in search? ===

Typing "ID:" followed by a number looks up a product by its internal database row ID. This is useful for support and debugging.

===== NDC Converter =====

=== Why can't I convert a plain 10-digit NDC without hyphens? ===

A 10-digit NDC without hyphens is ambiguous. The three possible segment configurations (4-4-2, 5-3-2, 5-4-1) cannot be distinguished without the hyphens. Always include hyphens when entering a 10-digit NDC.

=== What's the difference between 10-digit and 11-digit NDC? ===

The 10-digit NDC is the format printed on drug labels with variable segment lengths. The 11-digit NDC is a standardized format (always 5-4-2) used in billing and claims systems, created by zero-padding the short segment.

===== Support =====

=== How do I report a data issue? ===

On any [[ndc-lookup:product-detail|product detail]] page, tap **Report an Issue** at the bottom. This opens an email with the product information pre-filled.

=== How do I contact support? ===

See [[ndc-lookup:contact|Contact Support]] or email [[support@mccanalytics.com|support@mccanalytics.com]].