Benchmark: startsWith vs includes (when no match)

Tests:

"Hi this is a test, would you look at that".startsWith("bonjour")
"Hi this is a test, would you look at that".startsWith("bonjour")
"Hi this is a test, would you look at that".includes("bonjour")
"Hi this is a test, would you look at that".includes("bonjour")

Historical Performance Data aggregated from 31 community runs

Desktop Results:

Chrome 31 runs

"Hi this is a test, would you look at that".includes("bonjour")

197.0M/s

"Hi this is a test, would you look at that".startsWith("bonjour")

119.7M/s

Fastest: "Hi this is a test, would you look at that".includes("bonjour") (1.6x faster)

View exact numbers

✓ "Hi this is a test, would you look at that".includes("bonjour"): 196,953,792 ops/sec
• "Hi this is a test, would you look at that".startsWith("bonjour"): 119,709,584 ops/sec

Results show median performance across all community submissions. Run this benchmark yourself to verify on your device.

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
"Hi this is a test, would you look at that".startsWith("bonjour")
"Hi this is a test, would you look at that".includes("bonjour")

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 12 days ago)

User agent: Mozilla/5.0 (Android 17; Mobile; rv:152.0) Gecko/152.0 Firefox/152.0

Browser/OS: Firefox Mobile 152 on Android

View result in a separate tab

"Hi this is a test, would you look at that".includes("bonjour")

1396.2M/s

"Hi this is a test, would you look at that".startsWith("bonjour")

1388.9M/s

View exact numbers

Test name	Executions per second
✓ "Hi this is a test, would you look at that".includes("bonjour")	1,396,161,664 Ops/sec
"Hi this is a test, would you look at that".startsWith("bonjour")	1,388,927,744 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 its options.

**What is being tested?**

The benchmark is testing two string comparison methods: `startsWith` and `includes`. The test cases are comparing the performance of these two methods when there is no match in the string.

**Options compared**

The two options being compared are:

1. `startsWith`: This method checks if the string starts with a specified substring.
2. `includes`: This method checks if the string contains a specified substring.

**Pros and Cons**

* `startsWith`:
	+ Pros: Can be faster when the search pattern is at the beginning of the string, as it only needs to traverse a small portion of the string.
	+ Cons: May be slower for strings that contain the search pattern in the middle or at the end.
* `includes`:
	+ Pros: More flexible and can find the substring anywhere in the string, not just at the beginning.
	+ Cons: May be slower than `startsWith` when the search pattern is near the beginning of the string.

**Library usage**

There doesn't seem to be any library used in this benchmark. The test cases are using built-in JavaScript methods (`startsWith` and `includes`) without any additional dependencies.

**Special JS feature or syntax**

None mentioned.

**Benchmark preparation code**

The script preparation code is empty, which means that the benchmarking framework will likely generate a random string for testing.

**Other alternatives**

If this benchmark were to test different approaches, some alternatives could be:

* Using regular expressions (e.g., `RegExp.test`)
* Using a custom implementation of the comparison method
* Testing the performance of different browsers or environments

However, since the focus is on comparing `startsWith` and `includes`, these alternative approaches might not provide additional insights.

In summary, this benchmark tests the performance difference between two string comparison methods: `startsWith` and `includes`. The test cases are designed to find the substring "bonjour" in a random string.

startsWith vs includes (when no match) (version: 0)

Comparing performance of: `"Hi this is a test, would you look at that".startsWith("bonjour") vs "Hi this is a test, would you look at that".includes("bonjour")`

Created: 2 years ago by: Registered User

Go to the latest result

"Hi this is a test, would you look at that".startsWith("bonjour")

"Hi this is a test, would you look at that".includes("bonjour")

Historical Performance Data aggregated from 31 community runs

Desktop Results:

Chrome 31 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

startsWith vs includes (when no match) (version: 0)

Comparing performance of: "Hi this is a test, would you look at that".startsWith("bonjour") vs "Hi this is a test, would you look at that".includes("bonjour")

Created: 2 years ago by: Registered User

Go to the latest result

"Hi this is a test, would you look at that".startsWith("bonjour")

"Hi this is a test, would you look at that".includes("bonjour")

Historical Performance Data aggregated from 31 community runs

Desktop Results:

Chrome 31 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

Related benchmarks

Comparing performance of: `"Hi this is a test, would you look at that".startsWith("bonjour") vs "Hi this is a test, would you look at that".includes("bonjour")`