Benchmark: typeof vs boolean

Script Preparation code:

var obj = 'string';

Tests:

boolean
Boolean(obj)
typeof
typeof obj === 'string'

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
boolean
typeof

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/129.0.0.0 Safari/537.36

Browser/OS: Chrome 129 on Linux

View result in a separate tab

Test name	Executions per second
boolean	5281291.5 Ops/sec
typeof	9025607.0 Ops/sec

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

LLMs can make mistakes. Check important info.

I'd be happy to explain the benchmark and its components.

**Benchmark Overview**

The provided benchmark measures the performance difference between two approaches:

1. `Boolean(obj)`
2. `typeof obj === 'string'`

These two approaches are used to check if the value of `obj` is a string.

**Options Compared**

The options compared in this benchmark are:

* `Boolean(obj)`: This approach uses the `Boolean()` function to convert the value of `obj` to a boolean. If `obj` is a string, it will be converted to `true`. Otherwise, it will be converted to `false`.
* `typeof obj === 'string'`: This approach uses the `typeof` operator with the `===` equality operator to check if the type of `obj` is a string. If `obj` is a string, this condition will evaluate to `true`.

**Pros and Cons**

* **Boolean(obj)**:
	+ Pros: Simple and straightforward.
	+ Cons: It may be slower than `typeof obj === 'string'` because it involves an additional function call.
* **typeof obj === 'string'**:
	+ Pros: Faster, as it only checks the type of `obj`.
	+ Cons: More complex and harder to read.

**Other Considerations**

When comparing these two approaches, we should also consider other factors that might affect performance:

* The specific JavaScript engine used by the browser.
* The version of the browser.
* The hardware platform (e.g., desktop vs. mobile).
* The specific string value being tested (e.g., a short string vs. a long string).

**Library and Special JS Features**

Neither of these approaches uses any libraries or special JavaScript features beyond the basic syntax of the language.

However, it's worth noting that the `typeof` operator is part of the ECMAScript specification and is widely supported by modern browsers.

**Benchmark Preparation Code**

The preparation code provided for this benchmark is:
```javascript
var obj = 'string';
```
This code simply declares a variable `obj` and assigns it the string value `'string'`.

**Individual Test Cases**

There are two test cases:

1. **boolean**: This test case uses the `Boolean()` function to convert the value of `obj` to a boolean.
2. **typeof**: This test case uses the `typeof` operator with the `===` equality operator to check if the type of `obj` is a string.

**Latest Benchmark Result**

The latest benchmark result shows that:

* The `typeof obj === 'string'` approach executed at an average rate of 107,192,733 executions per second.
* The `Boolean(obj)` approach executed at an average rate of 256,668,474 executions per second.

This suggests that the `typeof obj === 'string'` approach is faster than the `Boolean(obj)` approach in this specific benchmark.

Related benchmarks:

typeof vs boolean (version: 0)

Comparing performance of: boolean vs typeof

Created: 3 years ago by: Guest

Jump to the latest result

boolean

typeof

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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