kotindia

Canonical Indian toolkit providing validators, formatters, checksum verification (Verhoeff, Luhn, GSTN base‑36), and PII maskers for 16 national identifiers, zero runtime dependencies, exhaustive tests.

#validation

Suggest an edit

JVM

iOS

GitHub stars0

Authorskotindia

Dependents0

LicenseApache License 2.0

Creation date5 months ago

Last activity4 months ago

Latest release0.1.0 (4 months ago)

GitHub repository GitHub pages Wiki page

KotIndia

Canonical Indian developer toolkit for Kotlin Multiplatform — validators, formatters, and maskers for PAN, Aadhaar, GSTIN, IFSC, UPI, and 12 more Indian system codes.

What is KotIndia?

KotIndia fills a verified gap in the Kotlin and Android ecosystem: as of 2026, no comprehensive, well-tested Kotlin Multiplatform library exists on Maven Central for validating and formatting Indian system codes. KotIndia provides format validation, checksum verification (Verhoeff for Aadhaar, Luhn for IMEI, GSTN base-36 for GSTIN), formatting, and PII masking for 16 Indian identifiers — all in a single, zero-runtime-dependency, pure Kotlin Multiplatform library licensed under Apache 2.0.

Version 0.1.0 ships the core module: 16 validators, formatters, and maskers for Android, JVM, and iOS targets. Zero runtime dependencies — pure Kotlin stdlib only. 100% line coverage on core. The compose UI component module and the upi deep-link module follow in Phase 2 and Phase 3 after core has adoption signal.

Install

Add the dependency in your Gradle Kotlin DSL build file:

dependencies {
    implementation("io.github.kotindia:core:0.1.0")
}

Make sure mavenCentral() is in your repositories block (Gradle docs):

repositories {
    mavenCentral()
}

Validators — quick reference

Validator	Format	Checksum	`mask()`?
`Mobile`	10 digits, prefix 6/7/8/9	None	YES
`Pincode`	6 digits, first digit 1–9	None	NO
`IFSC`	`[A-Z]{4}0[A-Z0-9]{6}`	None	NO
`PAN`	`[A-Z]{5}[0-9]{4}[A-Z]`, 4th-char category	None	YES
`Aadhaar`	12 digits, first digit 2–9	Verhoeff	YES
`AadhaarVID`	16 digits, first digit 2–9	Verhoeff	YES
`IMEI`	15 digits	Luhn	YES
`GSTIN`	15 chars: state + PAN + entity + Z + check	GSTN base-36	NO
`UAN`	12 digits	None	YES
`CIN`	21 chars: L/U + industry + state + year + class + reg	Structural	NO
`VPA`	`username@psp`, max 50 chars	None	NO
`DL`	State(2) + RTO(1–2) + year(4) + serial(7)	None	YES
`VehicleRC`	`[A-Z]{2}[0-9]{1,2}[A-Z]{1,3}[0-9]{4}`	None	NO
`Passport`	`[A-Z]\d{7}`	None	YES
`ESIC`	17 digits	None	YES
`TAN`	`[A-Z]{4}[0-9]{5}[A-Z]`	None	NO

Code examples

Aadhaar — validate, format, mask

import io.github.kotindia.*

Aadhaar.validate("234567890124")  // ValidationResult.Valid
Aadhaar.isValid("234567890124")   // true
Aadhaar.format("234567890124")    // "2345 6789 0124"
Aadhaar.mask("234567890124")      // "XXXXXXXX0124"

PAN — validate, format, mask

import io.github.kotindia.*

PAN.validate("ABCPE1234F")        // ValidationResult.Valid
PAN.validate("ABCZE1234F")        // ValidationResult.Invalid(reason=INVALID_CATEGORY)
PAN.format("abcpe1234f")          // "ABCPE1234F"
PAN.mask("ABCPE1234F")            // "XXXXXX234F"

GSTIN — validate, format

import io.github.kotindia.*

GSTIN.validate("27AAPFU0939F1ZV") // ValidationResult.Valid
GSTIN.format("27aapfu0939f1zv")   // "27AAPFU0939F1ZV"

Mobile — validate, format with country code, mask

import io.github.kotindia.*

Mobile.validate("9876543210")                              // ValidationResult.Valid
Mobile.isValid("+91 98765 43210")                          // true
Mobile.format("9876543210", withCountryCode = true)        // "+91 98765 43210"
Mobile.mask("9876543210")                                  // "XXXXXX3210"

IFSC — validate, format

import io.github.kotindia.*

IFSC.validate("HDFC0000001")      // ValidationResult.Valid
IFSC.format("hdfc0000001")        // "HDFC0000001"

ValidationResult — pattern matching

import io.github.kotindia.*

when (val result = Aadhaar.validate(userInput)) {
    is ValidationResult.Valid -> println("Valid Aadhaar")
    is ValidationResult.Invalid -> when (result.reason) {
        InvalidReason.EMPTY -> println("Input is empty")
        InvalidReason.WRONG_LENGTH -> println("Must be 12 digits")
        InvalidReason.INVALID_PREFIX -> println("First digit must be 2–9")
        InvalidReason.INVALID_CHECKSUM -> println("Verhoeff checksum failed")
        else -> println("Invalid: ${result.reason}")
    }
}

API documentation

Full API documentation (KDoc): https://kotindia.github.io/kotindia

Contributing

Contributions are welcome. Please read CONTRIBUTING.md for the code style guide, branch conventions, and the PR review checklist. All PRs must pass CI (build + test + lint + 100% coverage) before review.

License

Apache License 2.0. See LICENSE.

JVM

iOS