Credit Card Number Validator

#	Number	Valid	Type	MII	IIN
{{ i + 1 }}	{{ r.number }}	{{ r.is_valid ? 'Yes' : 'No' }}	{{ r.card_type }}	{{ r.mii }}	{{ r.iin }}

Validate credit card numbers quickly and accurately by providing single or bulk entries. The validator employs industry-standard techniques, including the Luhn checksum, to confirm structural integrity while simultaneously identifying issuing schemes, major-industry identifiers, and issuer identification numbers. Whether pasting raw text or importing a list file, you receive immediate feedback, empowering finance teams, auditors, and developers to verify data before processing transactions.

Robust input sanitation removes extraneous characters and automatically separates numbers presented on distinct lines, comma-delimited, or space-separated. Drag-and-drop functionality accepts plaintext or comma-separated value files, triggering validation on load without extra clicks. Status overlays guide users during import, and a concise summary reports valid versus invalid counts, ensuring large datasets are triaged swiftly without manual counting or external spreadsheets.

Detailed per-number analytics reveal card type, first six-digit issuer identifier, and single-digit MII classification, all displayed within an accessible, scroll-locked results table. Font-monospace formatting preserves readability, while color cues instantly highlight failures. Integrated query-parameter support retains input across sessions, enabling seamless bookmarking, sharing, and scripted automation workflows for testing suites, payment gateways, or compliance pipelines.

This section details the key capabilities, data structures, and algorithms employed by the validator.

Accepts newline, comma, and space-separated number lists
Drag-and-drop import for .txt and .csv datasets
Real-time validation with debounced processing for very large inputs
Implements Luhn checksum for structural integrity confirmation
Auto-detects Visa, Mastercard, AmEx, Discover, JCB, and regional schemes
Displays Major Industry Identifier and first six-digit IIN for each entry
Summary banner instantly reports valid versus invalid totals
Pure client-side logic ensures data never leaves the browser
Query-string persistence enables bookmarking and automated testing pipelines

Sample Number	Valid?	Scheme	MII	IIN
4111111111111111	Yes	Visa	Banking	411111
5500000000000004	Yes	Mastercard	Banking	550000
1234567812345670	No	Unknown	ISO/TC 68	123456

# Example JSON result
{
  "number": "4111111111111111",
  "is_valid": true,
  "card_type": "Visa",
  "mii": "Banking",
  "iin": "411111"
}

Follow these precise steps to validate one or thousands of credit-card numbers with confidence.

Open Credit Card Number Validator and locate the Credit-card numbers textarea inside the card.
Paste, type, or Tip drag-and-drop a .txt or .csv file containing numbers.
Review the overlay to confirm that the import has completed successfully.
Press Validate to initiate Luhn and scheme checks on all entries.
Observe the blue summary alert reporting valid and invalid totals.
Scroll through the results table to inspect individual outcomes, issuer data, and MII labels.
Caution Copy the updated URL if you need to share or revisit the same dataset later.

The answers below clarify common operational and policy questions.

What algorithm determines whether a number is valid?

The validator applies the Luhn checksum, doubling alternate digits from the right, subtracting nine when the product exceeds nine, and confirming that the total modulo 10 equals zero.

Does the tool identify prepaid, debit, or credit products?

It recognises the high-level scheme and IIN, but product tiering depends on issuer-specific subranges that are beyond the scope of public reference data.

Which file formats are supported for drag-and-drop import?

Plain-text files with extensions .txt and .csv, encoded in UTF-8 or ASCII, are fully supported. Binary formats and proprietary spreadsheets are ignored for safety.

Is any data transmitted to external servers during validation?

No. All parsing, checksum computation, and scheme detection occur entirely within your browser session; nothing is logged or transmitted externally.

Why are some valid-looking numbers flagged as “Unknown” type?

The number’s prefix does not match published IIN ranges for mainstream schemes. Private-label or newly issued ranges may appear until global registries are updated.

If results appear unexpected, consult the checklist below before escalating.

Zero results returned: Ensure the textarea is not empty and that entries are separated by whitespace, commas, or newlines.
“Invalid file type” alert: Confirm the imported document ends with .txt or .csv and contains plain text only.
Numbers flagged invalid yet accepted elsewhere: Verify that no hidden characters (e.g. non-breaking spaces) remain; re-copy in plain-text mode.
Slow validation on very large lists: Split the dataset into smaller segments or wait for the process banner to complete before interacting.
Browser tab freezes: Refresh the page and limit bulk validation to 50 000 lines per run.

Leverage these pro-level techniques to integrate the validator into advanced workflows.

Append ?rawInput=4111111111111111,5500000000000004 to the URL to pre-populate and auto-validate on load.
Embed the tool in documentation using an <iframe sandbox> attribute to preserve client-side isolation.
Run bulk checks offline by saving the page locally; all assets are self-contained via the Bootstrap CDN.
Combine browser console scripting with the exposed app instance for automated result extraction.
Style the results table further by injecting custom CSS into the developer tools for quick visual differentiation.

The definitions below clarify domain-specific terms used throughout the interface.

Luhn Algorithm: Mathematical checksum used to verify the validity of primary account numbers.
IIN: Issuer Identification Number; the first six digits identifying the issuing bank or institution.
MII: Major Industry Identifier; the initial digit classifying the industry of the issuer.
PAN: Primary Account Number; full sequence embossed or encoded on a payment card.
Checksum: Calculated value appended or derived from data to detect transcription errors.

Credit Card Number Validator

Credit-card numbers:

Embed this tool into your website using the following code: