Benchmark: toUpperCase vs toLowerCase - true

Script Preparation code:

var text = 'SOME ARE UPPER some are lower';

Tests:

toUpperCase
text.toUpperCase();
toLowerCase
text.toLowerCase();

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
toUpperCase
toLowerCase

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 7 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/140.0.0.0 Safari/537.36

Browser/OS: Chrome 140 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
toUpperCase	153070672.0 Ops/sec
toLowerCase	164432208.0 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 help explain the JavaScript microbenchmark provided by MeasureThat.net.

**Benchmark Description**

The benchmark is designed to compare the performance of two string methods: `toUpperCase()` and `toLowerCase()`. The test creates a sample string `text` with some uppercase and lowercase characters, and then uses these methods to modify it. The goal is to measure which method is faster in terms of execution time.

**Options Compared**

The benchmark compares two options:

1. **`toUpperCase()`**: This method converts all characters in the input string to uppercase.
2. **`toLowerCase()`**: This method converts all characters in the input string to lowercase.

**Pros and Cons of Each Approach**

* **`toUpperCase()`**:
	+ Pros: Can be faster for strings with a high proportion of uppercase characters, as it uses a single operation to convert all characters to uppercase.
	+ Cons: May be slower for strings with a high proportion of lowercase characters, as it needs to iterate over each character and perform the conversion individually.
* **`toLowerCase()`**:
	+ Pros: Can be faster for strings with a high proportion of lowercase characters, as it uses a single operation to convert all characters to lowercase.
	+ Cons: May be slower for strings with a high proportion of uppercase characters, as it needs to iterate over each character and perform the conversion individually.

**Library Used**

The benchmark does not explicitly use any libraries, but it relies on the built-in `String` methods `toUpperCase()` and `toLowerCase()`. These methods are part of the JavaScript Standard Library and do not require additional imports or setup.

**Special JS Feature or Syntax**

This benchmark does not include any special JavaScript features or syntax that would affect its execution. It simply uses standard JavaScript methods to perform the comparison.

**Other Considerations**

When comparing these two methods, it's worth noting that `toUpperCase()` is often faster than `toLowerCase()` because it can use a single operation to convert all characters to uppercase, whereas `toLowerCase()` needs to iterate over each character and perform the conversion individually. However, the actual performance difference between the two methods will depend on the specific input string and the JavaScript engine being used.

**Alternatives**

If you want to create a similar benchmark for other string methods or operations, here are some alternatives:

* Measure the performance of `trim()`, `padStart()`, and `padEnd()` using different input strings.
* Compare the performance of regular expressions (e.g., `RegExp.test()`, `RegExp.exec()`) with simple string matching techniques.
* Create a benchmark to compare the performance of array methods (e.g., `Array.prototype.forEach()`, `Array.prototype.map()`) with object methods (e.g., `Object.keys()`, `Object.values()`).

Related benchmarks:

toUpperCase vs toLowerCase - true (version: 0)

Comparing performance of: toUpperCase vs toLowerCase

Created: one year ago by: Guest

Jump to the latest result

toUpperCase

toLowerCase

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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