Benchmark: toFixed vs Math.round

Script Preparation code:

var someFloat = 0.123456789;

Tests:

toFixed
someFloat.toFixed(4);
Math.round
Math.round(someFloat)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
toFixed
Math.round

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 6 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/141.0.0.0 Safari/537.36

Browser/OS: Chrome 141 on Windows

View result in a separate tab

Test name	Executions per second
toFixed	7652530.0 Ops/sec
Math.round	100733944.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks and explain what's happening in this specific benchmark.

**What is being tested?**

The benchmark is comparing two ways to round a decimal number: `toFixed` and `Math.round`. The test case creates a floating-point number `someFloat` with a value of 0.123456789, which has 8 significant digits.

The goal is to measure the performance difference between these two rounding methods on different JavaScript engines.

**Options being compared**

There are two options being tested:

1. **toFixed**: This method returns a string representation of the number, rounded to the specified decimal places (in this case, 4). The resulting string can be either positive or negative.
2. **Math.round**: This method returns an integer value, which is the closest integer to the input floating-point number.

**Pros and Cons**

Here's a brief analysis of each approach:

* **toFixed**: Pros:
	+ Can produce more accurate results, especially for larger decimal numbers.
	+ Allows for customization of the rounding precision.
* Cons:
	+ Returns a string value, which can be slower to process than integers.
	+ May introduce unnecessary overhead due to string creation and manipulation.
* **Math.round**: Pros:
	+ Returns an integer value, which is generally faster to process than strings.
	+ More concise and efficient than using `toFixed`.
* Cons:
	+ Can lead to rounding errors, especially for numbers with a large number of decimal places.

**Library usage**

The benchmark uses the `someFloat` variable, but it doesn't explicitly define what library or functionality is being used. However, based on the context, we can assume that the JavaScript engine's built-in arithmetic functions are being used.

**Special JS feature/syntax**

There isn't any specific special JS feature or syntax being tested in this benchmark. The focus is solely on comparing two rounding methods.

**Other alternatives**

If you were to modify this benchmark, here are some alternative options to consider:

* **NaN (Not a Number)**: You could test how each method handles NaN values.
* **Infinity**: You could test how each method handles Infinity values.
* **Different rounding modes**: Depending on the context, you might want to test different rounding modes, such as "half-to-even" or "round half away from zero".
* **Large decimal numbers**: You could increase the precision of `someFloat` and see how performance changes with more significant digits.

Keep in mind that these alternatives would require modifications to the benchmark definition and script preparation code.

Related benchmarks:

toFixed vs Math.round (version: 0)

Comparing performance of: toFixed vs Math.round

Created: 5 years ago by: Guest

Jump to the latest result

toFixed

Math.round

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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