Benchmark: String to number, parseInt, +, or * 1

Script Preparation code:

var n = [
    "0",
    "1",
    "2",
    "3",
    "4",
    "5",
    "6",
    "7",
    "8",
    "9",
    "10",
    "11",
    "12",
    "13",
    "14",
    "15",
    "16",
    "17",
    "18",
    "19",
    "20",
    "21",
    "22",
    "23",
    "24",
    "25",
    "26",
    "27",
    "28",
    "29",
    "30",
    "31",
    "32",
    "33",
    "34",
    "35",
    "36",
    "37",
    "38",
    "39",
    "40",
    "41",
    "42",
    "43",
    "44",
    "45",
    "46",
    "47",
    "48",
    "49",
    "50",
    "51",
    "52",
    "53",
    "54",
    "55",
    "56",
    "57",
    "58",
    "59",
    "60",
    "61",
    "62",
    "63",
    "64",
    "65",
    "66",
    "67",
    "68",
    "69",
    "70",
    "71",
    "72",
    "73",
    "74",
    "75",
    "76",
    "77",
    "78",
    "79",
    "80",
    "81",
    "82",
    "83",
    "84",
    "85",
    "86",
    "87",
    "88",
    "89",
    "90",
    "91",
    "92",
    "93",
    "94",
    "95",
    "96",
    "97",
    "98",
    "99",
];

Tests:

parseInt
let i = 0; while (i < 10000) { i++; n.map((s) => parseInt(s)); }
+stringVar
let i = 0; while (i < 10000) { i++; n.map((s) => +s); }
stringVar * 1
let i = 0; while (i < 10000) { i++; n.map((s) => s * 1); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
parseInt
+stringVar
stringVar * 1

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:130.0) Gecko/20100101 Firefox/130.0

Browser/OS: Firefox 130 on Mac OS X 10.15

View result in a separate tab

Test name	Executions per second
parseInt	67.1 Ops/sec
+stringVar	73.1 Ops/sec
stringVar * 1	80.0 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what's being tested, compared, and the pros and cons of each approach.

**Benchmark Overview**

The benchmark measures the performance of three different methods for casting a string to a number in JavaScript:

1. `parseInt`: Converts a string to an integer using the `parseInt()` function.
2. `+stringVar`: Performs implicit type conversion by adding 0 to the string variable (essentially converting it to a number).
3. `stringVar * 1`: Multiplies the string variable by 1, which also converts it to a number.

**Comparison**

The benchmark compares the performance of these three methods on a large dataset (`n`) containing strings from "0" to "100". The test cases are identical except for the method being tested.

**Pros and Cons**

Here's a brief overview of each method:

1. `parseInt`:
	* Pros: Well-established, widely supported, and relatively fast.
	* Cons: May not work as expected if the input string is not in a numeric format.
2. `+stringVar`:
	* Pros: Simple and easy to understand, works with most numeric strings.
	* Cons: May be slower than `parseInt` due to the overhead of implicit type conversion.
3. `stringVar * 1`:
	* Pros: Fast and efficient, as it leverages the language's arithmetic operations.
	* Cons: Less intuitive for developers, may not work with non-numeric strings.

**Library/Functionality Used**

In this benchmark, no specific library or functionality is used beyond the built-in JavaScript functions `parseInt()` and implicit type conversion (`+stringVar`).

**Special JS Feature/Syntax**

There's no special JavaScript feature or syntax being tested in this benchmark. The focus is solely on the performance comparison of these three methods.

**Other Alternatives**

If you're looking for alternative ways to convert strings to numbers, consider:

1. Using a library like ` numeral.js` which provides more advanced numeric formatting and parsing capabilities.
2. Implementing your own string-to-number conversion function using regular expressions or other techniques.
3. Leveraging modern JavaScript features like template literals (`${expression}`) or the `Number()` function.

Keep in mind that these alternatives may not provide significant performance benefits over the original methods being compared, but they can offer additional functionality and flexibility for specific use cases.

I hope this explanation helps!

Related benchmarks:

String to number, parseInt, +, or * 1 (version: 0)

Which method of casting a string to a number is fastest

Comparing performance of: parseInt vs +stringVar vs stringVar * 1

Created: 2 years ago by: Registered User

Jump to the latest result

parseInt

+stringVar

stringVar * 1

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):