BigInt vs. parseInt in JavaScript: Working with Numbers

Hy everyone, Welcome back to my blog😊.

I was solving a leet code question about a week ago and I had the algorithm ready passing all three sample test cases, I tried submitting and the solution wasn't accepted for test cases with extremely large numbers😢. I tried to work around it while still using parseInt and I just couldn't get it right. After looking at other people's solutions, I discovered BigInt!😤

JavaScript comes with various tools for working with numbers and two common methods used for handling numbers are BigInt and parseInt. In this article, we'll delve into the differences between BigInt and parseInt, explore their use cases, and understand when to choose one over the other.

Understanding parseInt

parseInt is a built-in JavaScript function used to parse a string and convert it into an integer.

Usage of parseInt

By default, parseInt assumes base 10 (decimal) conversion. You can specify a different base by passing it as the second argument.

const decimalValue = parseInt("123"); // Result: 123 
const hexValue = parseInt("1A", 16); // Result: 26

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Understanding BigInt

Introduced in ECMAScript 2020 (ES11), BigInt is a numeric primitive that allows you to represent and work with arbitrarily large integers. This is especially useful when dealing with numbers that exceed JavaScript's 64-bit double-precision floating-point representation.

Declaring BigInt

To declare a BigInt literal, append an n to the end of an integer or use the BigInt() constructor.

const bigIntValue = 1234567890123456789012345678901234567890n;

Operations with BigInt

BigInt supports standard arithmetic operations, just like regular numbers.

const a = 12345n;
const b = 67890n;

const sum = a + b; // Result: 80235n

Differences and Use Cases

Now, let's explore the key differences between BigInt and parseInt and when to use each:

1. Numeric Range

• BigInt: Suitable for very large integer values. It can handle numbers beyond the limits of regular JavaScript numbers.

• parseInt: Limited to 32-bit signed integers, which means it has a range of approximately -2 billion to +2 billion.

2. Data Type

• BigInt: Represents numbers as a distinct data type. Operations involving BigInt values always produce BigInt results.

• parseInt: Converts strings into regular JavaScript numbers (64-bit double-precision floating-point), which can lead to precision loss for large integers.

3. Use Cases

• BigInt is ideal for scenarios where precision matters, such as cryptography, financial calculations, or when dealing with unique identifiers that are large integers.

• parseInt is more suitable for parsing user input like form values or reading numbers from strings in common use cases.

4. Compatibility

• BigInt: Requires modern JavaScript environments that support ES11 (or later) features. It may not work in older browsers or environments.

• parseInt: Supported in all JavaScript environments, making it more compatible for broader use.

Conclusion

In summary, BigInt and parseInt serve distinct purposes in JavaScript. Choose BigInt when you need to work with extremely large integers, maintain precision, or deal with modern JavaScript environments that support it. Use parseInt for common parsing tasks and when compatibility across various JavaScript environments is essential.

By understanding the differences and use cases of BigInt and parseInt, you'll be better equipped to handle numeric data effectively in your JavaScript applications.

Thank you all for reading!

Till we see again in my next post, byeeee💜💜.