YouTubeID for Go

Generate YouTube-style short IDs from numbers. Lightweight, fast, and reversible base62 encoder with optional obfuscation.

Other programming languages

• PHP: kvz/youtube-id
• Python: wow-apps/youtube-id-py
• TypeScript: wow-apps/youtube-id-ts
• Go: wow-apps/youtube-id-go

Features

• Lightweight - Zero dependencies, pure Go
• Fast - Simple base62 encoding/decoding
• Reversible - Encode and decode without data loss
• Obfuscation - Optional secure key to shuffle the dictionary
• Type-safe - Idiomatic Go with proper error handling

Installation

go get github.com/wow-apps/youtube-id-go

Quick Start

package main

import (
    "fmt"
    yid "github.com/wow-apps/youtube-id-go"
)

func main() {
    // Encode a number to a short string
    encoded, _ := yid.ToAlphanumeric(12345)
    fmt.Println(encoded) // -> "dnh"

    // Decode back to number
    decoded, _ := yid.ToNumeric("dnh")
    fmt.Println(decoded) // -> 12345
}

Usage

Basic Encoding/Decoding

import yid "github.com/wow-apps/youtube-id-go"

// Number to alphanumeric
yid.ToAlphanumeric(0)        // -> "a", nil
yid.ToAlphanumeric(61)       // -> "Z", nil
yid.ToAlphanumeric(62)       // -> "ba", nil
yid.ToAlphanumeric(12345)    // -> "dnh", nil
yid.ToAlphanumeric(999999)   // -> "eGGf", nil

// Alphanumeric to number
yid.ToNumeric("dnh")         // -> 12345, nil

With Secure Key (Obfuscation)

Use a secure key to shuffle the dictionary, making IDs harder to predict:

import yid "github.com/wow-apps/youtube-id-go"

// Without key
yid.ToAlphanumeric(12345)                              // -> "dnh"

// With secure key (different output)
yid.ToAlphanumeric(12345, yid.WithSecureKey("secret")) // -> different value

// Decode with the same key
yid.ToNumeric(encoded, yid.WithSecureKey("secret"))    // -> 12345

Case Transformation

import yid "github.com/wow-apps/youtube-id-go"

yid.ToAlphanumeric(12345, yid.WithTransform(yid.TransformUpper)) // -> "DNH"
yid.ToAlphanumeric(12345, yid.WithTransform(yid.TransformLower)) // -> "dnh"

Encoder for Repeated Operations

For repeated operations with the same settings, use the Encoder:

import yid "github.com/wow-apps/youtube-id-go"

// Create encoder with preset options
enc := yid.New(yid.WithSecureKey("my-secret"), yid.WithTransform(yid.TransformUpper))

// Encode
enc.Encode(12345)     // -> "HQJ" (transformed for display)
enc.EncodeRaw(12345)  // -> "hqj" (raw for storage/decoding)

// Decode
enc.Decode("hqj")     // -> 12345

API Reference

Functions

ToAlphanumeric(number int64, opts ...Option) (string, error)

Convert a number to a short alphanumeric string.

ToNumeric(alphanumeric string, opts ...Option) (int64, error)

Convert an alphanumeric string back to a number.

New(opts ...Option) *Encoder

Create a reusable Encoder instance with preset options.

Options

Option	Description
WithPadUp(int)	Padding value
WithSecureKey(string)	Key to shuffle dictionary
WithTransform(Transform)	Case transformation

Encoder Methods

Method	Description
Encode(number)	Convert number to alphanumeric (with transform)
EncodeRaw(number)	Convert number to alphanumeric (no transform)
Decode(alphanumeric)	Convert alphanumeric to number

Transform Constants

Constant	Description
TransformNone	No transformation
TransformUpper	Uppercase output
TransformLower	Lowercase output

Errors

Error	Description
ErrNegativeNumber	Input number is negative
ErrInvalidCharacter	Input contains invalid character

Use Cases

• URL shorteners - Convert database IDs to short URLs
• Public IDs - Hide sequential database IDs from users
• Share codes - Generate readable codes for sharing
• Invite links - Create short invitation tokens

Performance

The library uses base62 encoding (a-z, 0-9, A-Z) which provides:

Number Range	Output Length
0 - 61	1 character
62 - 3,843	2 characters
3,844 - 238,327	3 characters
238,328 - 14,776,335	4 characters

Contributing

Contributions are welcome! Please read our Contributing Guidelines and Code of Conduct.

# Clone and setup
git clone https://github.com/wow-apps/youtube-id-go.git
cd youtube-id-go

# Run tests
go test -v -race ./...

# Run tests with coverage
go test -v -race -coverprofile=coverage.out ./...
go tool cover -html=coverage.out

Credits

A Go port of the YouTube-style ID generator originally created by Kevin van Zonneveld and contributors.

License

MIT (c) Oleksii Samara, Kevin van Zonneveld