Benchmark: Date.valueOf vs Date.getTime() vs Number vs unary STRING

Tests:

getTime
const a = new Date("2013/09/05 15:34:00").getTime()
valueOf
const a = new Date("2013/09/05 15:34:00").valueOf()
Number(new Date())
Number(new Date("2013/09/05 15:34:00"))
unary
+new Date("2013/09/05 15:34:00")

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
getTime
valueOf
Number(new Date())
unary

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:138.0) Gecko/20100101 Firefox/138.0

Browser/OS: Firefox 138 on Mac OS X 10.15

View result in a separate tab

valueOf

9.8M/s

getTime

9.7M/s

Number(new Date())

6.5M/s

unary

6.3M/s

View exact numbers

Test name	Executions per second
✓ valueOf	9,760,776 Ops/sec
getTime	9,711,235 Ops/sec
Number(new Date())	6,481,924 Ops/sec
unary	6,297,623 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 benchmarks.

**What is tested?**

The provided JSON represents a benchmark test suite that compares the performance of four different approaches:

1. `Date.valueOf()`: Returns the number of milliseconds since the Unix Epoch (January 1, 1970) for the specified date.
2. `Date.getTime()`: Returns the number of milliseconds since the Unix Epoch for the specified date in UTC time zone.
3. `Number(new Date())`: Converts a `Date` object to a number representing the number of milliseconds since the Unix Epoch.
4. Unary `+new Date()` (often referred to as " unary plus"): A simple expression that converts a `Date` object to a number.

These approaches are being tested for their performance in different scenarios, likely to determine which one is the fastest and most efficient.

**Options compared**

The benchmark compares the execution speed of each approach:

* `getTime()` vs `valueOf()`: Which method returns the correct result faster?
* `Number(new Date())` vs Unary `+new Date()`: How does the conversion to a number affect performance?

**Pros and Cons**

Here's a brief summary of the pros and cons of each approach:

1. **Date.valueOf()**:
	* Pros: Simple, widely supported, and works well for most use cases.
	* Cons: Returns milliseconds since the Unix Epoch, not necessarily in UTC time zone, which can lead to incorrect results if used with non-UTC dates.
2. **Date.getTime()**:
	* Pros: Returns milliseconds since the Unix Epoch in UTC time zone, providing more accurate results when working with dates across different time zones.
	* Cons: May be slower due to the additional complexity of calculating the UTC offset.
3. **Number(new Date())**:
	* Pros: Simple and widely supported, but may incur a small performance overhead due to unnecessary conversions.
	* Cons: Returns milliseconds since the Unix Epoch in the local time zone, which can lead to incorrect results when working with dates across different time zones.
4. **Unary +new Date()`:
	* Pros: Simple and fast, as it directly converts the `Date` object to a number without any additional complexity.
	* Cons: May not work correctly for certain use cases (e.g., when using `NaN` or invalid dates).

**Library used**

None of the approaches explicitly use a library. However, the benchmark might be using some internal functions or methods provided by JavaScript engines or browsers that are not directly exposed to users.

**Special JS feature or syntax**

The benchmark uses a special JavaScript feature: **unary plus (`+new Date()`)**, which is not commonly used in everyday programming. This syntax is an example of the "operator overloading" technique, where an operator (in this case, `+`) is used to perform a specific operation on an object or value.

**Other alternatives**

While not explicitly mentioned in the benchmark, other approaches could be explored for comparison:

* Using `new Date().getTimezoneOffset()` instead of `Date.getTime()`
* Implementing custom date arithmetic functions
* Comparing performance with different JavaScript engines or browsers

Keep in mind that these alternatives might introduce additional complexity and may not be as widely supported or optimized.

Date.valueOf vs Date.getTime() vs Number vs unary STRING (version: 0)

Comparing performance of: `getTime vs valueOf vs Number(new Date()) vs unary`

Created: 3 years ago by: Guest

Go to the latest result

getTime

valueOf

Number(new Date())

unary

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

Date.valueOf vs Date.getTime() vs Number vs unary STRING (version: 0)

Comparing performance of: getTime vs valueOf vs Number(new Date()) vs unary

Created: 3 years ago by: Guest

Go to the latest result

getTime

valueOf

Number(new Date())

unary

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: `getTime vs valueOf vs Number(new Date()) vs unary`