Sqids (pronounced "squids") is a small library that lets you generate YouTube-looking IDs from numbers. It's good for link shortening, fast & URL-safe ID generation and decoding back into numbers for quicker database lookups.

Features:

• Encode multiple numbers - generate short IDs from one or several non-negative numbers
• Quick decoding - easily decode IDs back into numbers
• Unique IDs - generate unique IDs by shuffling the alphabet once
• ID padding - provide minimum length to make IDs more uniform
• URL safe - auto-generated IDs do not contain common profanity
• Randomized output - Sequential input provides nonconsecutive IDs
• Many implementations - Support for 40+ programming languages
• Header-only library - Simply drop the include directory into your project root

🧰 Use-cases

Good for:

• Generating IDs for public URLs (eg: link shortening)
• Generating IDs for internal systems (eg: event tracking)
• Decoding for quicker database lookups (eg: by primary keys)

Not good for:

• Sensitive data (this is not an encryption library)
• User IDs (can be decoded revealing user count)

🚀 Getting started

Installing

Note This step is fully optional. The easiest way to use this library is to merge the include directory into your project root and directly include the sqids.hpp header:

#include "include/sqids/sqids.hpp"

To install the headers on your system using CMake, run:

mkdir -p build
cd build
cmake ..
cmake --build . --config Release --target install

The last command typically needs to run as sudo.

(By default, the headers will be installed to include/sqids/, relative to the CMake install prefix, which is usually /usr/local/ on Linux/Unix.)

Including the library

In your code, include the library with:

#include <sqids/sqids.hpp>

For CMake-based projects, a minimal CMakeLists.txt configuration may consist of the following:

project("sqids-example")

find_package(sqids CONFIG REQUIRED)

add_executable(sqids-example main.cpp)
target_link_libraries(sqids-example INTERFACE sqids)

Running the tests

cmake -S . -B build 
cmake --build build
cd build 
ctest -V

👩‍💻 Examples

Encoding:

    sqidscxx::Sqids sqids;

    auto id = sqids.encode({ 1, 2, 3 });

Decoding:

    sqidscxx::Sqids sqids;

    auto numbers = sqids.decode("86Rf07");

    for (auto number : numbers) {
        std::cout << number << std::endl;
    }

Enforce a minimum length for IDs:

    sqidscxx::Sqids sqids({ minLength: 10 });

    auto id = sqids.encode({ 1, 2, 3 });

    std::cout << id << std::endl;

Output is 86Rf07xd4z.

Randomize IDs by providing a custom alphabet:

    sqidscxx::Sqids sqids({ alphabet: "FxnXM1kBN6cuhsAvjW3Co7l2RePyY8DwaU04Tzt9fHQrqSVKdpimLGIJOgb5ZE" });

    auto id = sqids.encode({ 1, 2, 3 });

    std::cout << id << std::endl;

Output is B4aajs.

Prevent specific words from appearing anywhere in the auto-generated IDs:

    sqidscxx::Sqids sqids({ blocklist: {{ "86Rf07" }} });

    auto id = sqids.encode({ 1, 2, 3 });

    std::cout << id << std::endl;

Output is se8ojk.

📝 License

MIT