var intvalue = Math.floor( floatvalue );
var intvalue = Math.ceil( floatvalue );
var intvalue = Math.round( floatvalue );
// `Math.trunc` was added in ECMAScript 6
var intvalue = Math.trunc( floatvalue );
Math object reference
Examples
Positive// value=x // x=5 5<x<5.5 5.5<=x<6
Math.floor(value) // 5 5 5
Math.ceil(value) // 5 6 6
Math.round(value) // 5 5 6
Math.trunc(value) // 5 5 5
parseInt(value) // 5 5 5
~~value // 5 5 5
value | 0 // 5 5 5
value >> 0 // 5 5 5
value >>> 0 // 5 5 5
value - value % 1 // 5 5 5
// value=x // x=-5 -5>x>=-5.5 -5.5>x>-6
Math.floor(value) // -5 -6 -6
Math.ceil(value) // -5 -5 -5
Math.round(value) // -5 -5 -6
Math.trunc(value) // -5 -5 -5
parseInt(value) // -5 -5 -5
value | 0 // -5 -5 -5
~~value // -5 -5 -5
value >> 0 // -5 -5 -5
value >>> 0 // 4294967291 4294967291 4294967291
value - value % 1 // -5 -5 -5
// x = Number.MAX_SAFE_INTEGER/10 // =900719925474099.1
// value=x x=900719925474099 x=900719925474099.4 x=900719925474099.5
Math.floor(value) // 900719925474099 900719925474099 900719925474099
Math.ceil(value) // 900719925474099 900719925474100 900719925474100
Math.round(value) // 900719925474099 900719925474099 900719925474100
Math.trunc(value) // 900719925474099 900719925474099 900719925474099
parseInt(value) // 900719925474099 900719925474099 900719925474099
value | 0 // 858993459 858993459 858993459
~~value // 858993459 858993459 858993459
value >> 0 // 858993459 858993459 858993459
value >>> 0 // 858993459 858993459 858993459
value - value % 1 // 900719925474099 900719925474099 900719925474099
// x = Number.MAX_SAFE_INTEGER/10 * -1 // -900719925474099.1
// value = x // x=-900719925474099 x=-900719925474099.5 x=-900719925474099.6
Math.floor(value) // -900719925474099 -900719925474100 -900719925474100
Math.ceil(value) // -900719925474099 -900719925474099 -900719925474099
Math.round(value) // -900719925474099 -900719925474099 -900719925474100
Math.trunc(value) // -900719925474099 -900719925474099 -900719925474099
parseInt(value) // -900719925474099 -900719925474099 -900719925474099
value | 0 // -858993459 -858993459 -858993459
~~value // -858993459 -858993459 -858993459
value >> 0 // -858993459 -858993459 -858993459
value >>> 0 // 3435973837 3435973837 3435973837
value - value % 1 // -900719925474099 -900719925474099 -900719925474099
Top answer 1 of 16
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var intvalue = Math.floor( floatvalue );
var intvalue = Math.ceil( floatvalue );
var intvalue = Math.round( floatvalue );
// `Math.trunc` was added in ECMAScript 6
var intvalue = Math.trunc( floatvalue );
Math object reference
Examples
Positive// value=x // x=5 5<x<5.5 5.5<=x<6
Math.floor(value) // 5 5 5
Math.ceil(value) // 5 6 6
Math.round(value) // 5 5 6
Math.trunc(value) // 5 5 5
parseInt(value) // 5 5 5
~~value // 5 5 5
value | 0 // 5 5 5
value >> 0 // 5 5 5
value >>> 0 // 5 5 5
value - value % 1 // 5 5 5
// value=x // x=-5 -5>x>=-5.5 -5.5>x>-6
Math.floor(value) // -5 -6 -6
Math.ceil(value) // -5 -5 -5
Math.round(value) // -5 -5 -6
Math.trunc(value) // -5 -5 -5
parseInt(value) // -5 -5 -5
value | 0 // -5 -5 -5
~~value // -5 -5 -5
value >> 0 // -5 -5 -5
value >>> 0 // 4294967291 4294967291 4294967291
value - value % 1 // -5 -5 -5
// x = Number.MAX_SAFE_INTEGER/10 // =900719925474099.1
// value=x x=900719925474099 x=900719925474099.4 x=900719925474099.5
Math.floor(value) // 900719925474099 900719925474099 900719925474099
Math.ceil(value) // 900719925474099 900719925474100 900719925474100
Math.round(value) // 900719925474099 900719925474099 900719925474100
Math.trunc(value) // 900719925474099 900719925474099 900719925474099
parseInt(value) // 900719925474099 900719925474099 900719925474099
value | 0 // 858993459 858993459 858993459
~~value // 858993459 858993459 858993459
value >> 0 // 858993459 858993459 858993459
value >>> 0 // 858993459 858993459 858993459
value - value % 1 // 900719925474099 900719925474099 900719925474099
// x = Number.MAX_SAFE_INTEGER/10 * -1 // -900719925474099.1
// value = x // x=-900719925474099 x=-900719925474099.5 x=-900719925474099.6
Math.floor(value) // -900719925474099 -900719925474100 -900719925474100
Math.ceil(value) // -900719925474099 -900719925474099 -900719925474099
Math.round(value) // -900719925474099 -900719925474099 -900719925474100
Math.trunc(value) // -900719925474099 -900719925474099 -900719925474099
parseInt(value) // -900719925474099 -900719925474099 -900719925474099
value | 0 // -858993459 -858993459 -858993459
~~value // -858993459 -858993459 -858993459
value >> 0 // -858993459 -858993459 -858993459
value >>> 0 // 3435973837 3435973837 3435973837
value - value % 1 // -900719925474099 -900719925474099 -900719925474099
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Bitwise OR operator
A bitwise or operator can be used to truncate floating point figures and it works for positives as well as negatives:
function float2int (value) {
return value | 0;
}
Results
float2int(3.1) == 3
float2int(-3.1) == -3
float2int(3.9) == 3
float2int(-3.9) == -3
Performance comparison?
I've created a JSPerf test that compares performance between:
Math.floor(val)val | 0bitwise OR~~valbitwise NOTparseInt(val)
that only works with positive numbers. In this case you're safe to use bitwise operations well as Math.floor function.
But if you need your code to work with positives as well as negatives, then a bitwise operation is the fastest (OR being the preferred one). This other JSPerf test compares the same where it's pretty obvious that because of the additional sign checking Math is now the slowest of the four.
Note
As stated in comments, BITWISE operators operate on signed 32bit integers, therefore large numbers will be converted, example:
1234567890 | 0 => 1234567890
12345678901 | 0 => -539222987
Reddit
reddit.com › r/programmeranimemes › hey javascript, can you turn my float into int properly?
[Mature Content] r/ProgrammerAnimemes on Reddit: Hey JavaScript, can you turn my float into int properly?
February 3, 2022 - IEEE 754?) first, then to int. If you want float to int, you have to use Math.round() or something.
Videos
05:54
How to Use parseInt and parseFloat - YouTube
01:30
Understanding JavaScript Conversion: From Integer to Float - YouTube
08:23
How to Format Numbers with toFixed() and parseFloat() in JavaScript ...
01:56
Parsing Integer & Float in Javascript - 24 - YouTube
01:16
How to Convert an Integer with n Decimal Places to a Float in ...
08:13
ParseFloat Method JavaScript - YouTube
GeeksforGeeks
geeksforgeeks.org › javascript › how-to-convert-a-float-number-to-the-whole-number-in-javascript
How to Convert a Float Number to the Whole Number in JavaScript? - GeeksforGeeks
July 11, 2025 - ... // float value is 4.59; let x = 4.59; let z = Math.round(x); console.log("Converted value of " + x + " is " + z); ... Return the integer part of a floating-point number by removing the fractional digits.
Code Highlights
code-hl.com › home › javascript › tutorials
5 Easy Ways to Convert JavaScript Float to Int | Code Highlights
June 4, 2024 - The bitwise OR operator can also convert a float to an integer by truncating the decimal part. ... All these methods are compatible with major web browsers, including Chrome, Firefox, Safari, Edge, and Internet Explorer. This ensures that your code will run smoothly across different environments. In this tutorial, we explored five simple methods to convert a JavaScript float to an int:
MDN Web Docs
developer.mozilla.org › en-US › docs › Web › JavaScript › Reference › Global_Objects › Number
Number - JavaScript | MDN
A number literal like 37 in JavaScript code is a floating-point value, not an integer. There is no separate integer type in common everyday use. (JavaScript also has a BigInt type, but it's not designed to replace Number for everyday uses.
Delft Stack
delftstack.com › home › howto › javascript › javascript float to int
How to Convert a Float Number to Int in JavaScript | Delft Stack
February 2, 2024 - We can apply the bitwise right shift operator (represented by >> characters). It will convert the float value to an integer. Underneath at the binary level, the bitwise right SHIFT operator shifts the binary bits of the operand to the right ...
MDN Web Docs
developer.mozilla.org › en-US › docs › Web › JavaScript › Reference › Global_Objects › parseFloat
parseFloat() - JavaScript | MDN
A floating point number parsed from the given string, or NaN when the first non-whitespace character cannot be converted to a number. Note: JavaScript does not have the distinction of "floating point numbers" and "integers" on the language level. parseInt() and parseFloat() only differ in their parsing behavior, but not necessarily their return values.
TutorialsPoint
tutorialspoint.com › how-do-i-convert-a-float-number-to-a-whole-number-in-javascript
How do I convert a float number to a whole number in JavaScript?
In the above output users can see that Math.trunc() method has removed the decimal part and Math.round() method has rounded the number to nearest integer. In this approach, we will use the parseInt() method. The parseInt() method extracts the whole number from the float number or string in ...
Internet Computer Developer Forum
forum.dfinity.org › developers
Convert a Float number to an Int type - Developers - Internet Computer Developer Forum
June 10, 2024 - I am trying to convert a float number to an integer. The reason is that I want the E8S equivalent of 1 ICP of a value, for example 1.15. This should be 115_000_000, but the function returns 114_000_000. Other values are calculated correctly, for example 1.25 = 125_000_000 or 0.9 = 90_000_000. public func convertFloatToNat(x: Float): async Int { let ONE_ICP_IN_E8S = 100_000_000; Debug.print("convertFloatToNat "#debug_show(x)); let a = x * 100; Debug.print("float x 100 = "#...
Unity
discussions.unity.com › unity engine
[SOLVED] typecast float to int in javascript? - Unity Engine - Unity Discussions
September 18, 2009 - A forum search has lead me to think it’s not doable. “as” only works on reference types and Unity doesn’t dig var f1 : float = 3.14; var myVar : int = (int)f1; or var f1 : float = 3.14; var myVar : int = int(f1);…
W3Schools
w3schools.com › js › js_numbers.asp
JavaScript Numbers
JavaScript numbers are always stored as double precision floating point numbers, following the international IEEE 754 standard. This format stores numbers in 64 bits, where the number (the fraction) is stored in bits 0 to 51, the exponent in bits 52 to 62, and the sign in bit 63:
Byby
byby.dev › js-float-to-int
How to convert float to integer in JavaScript
You can use various methods that either round, truncate, or parse the float value. Depending on your specific use case, you can choose the most appropriate method: Using Math.trunc(). This method returns the integer part of a number by removing any fractional digits. In other words, it truncates (cuts off) the dot and the digits to the right of it, no matter whether the argument is a positive or negative number.
Itsourcecode
itsourcecode.com › home › converting floats to integers in javascript: 10 effective ways
Converting Floats to Integers in JavaScript: 10 Effective Ways
July 27, 2023 - Find out the different methods to achieve JavaScript float to int conversion effectively. Do you want to know how to convert float numbers...
Javascripts
javascripts.com › convert-floats-to-integers-in-javascript
How to Convert Floats to Integers in JavaScript
June 23, 2023 - The Math.floor() method in JavaScript is used to round down a number to the nearest integer. It will convert a floating-point number to an integer by cutting off the decimal portion, effectively ‘flooring’ the value.
Codemia
codemia.io › knowledge-hub › path › how_do_i_convert_a_float_number_to_a_whole_number_in_javascript
How do I convert a float number to a whole ...
Enhance your system design skills with over 120 practice problems, detailed solutions, and hands-on exercises
W3docs
w3docs.com › javascript
How to Convert a Float Number to Whole Number in JavaScript
The parseInt() function parses the string argument and returns an integer of the given radix. ... The ~~ operator rounds a number towards 0 if the operand is a number and it’s not NaN or Infinity. ... The OR operator rounds a number towards 0. ... There are two types of numbers in JavaScript: Regular and BigInt. Regular is also known as “double-precision floating-point numbers”. The math is a built-in object which has properties and methods for mathematical constants and functions.
Javascriptf1
javascriptf1.com › snippet › convert-a-float-number-to-integer-in-javascript
Convert a float number to integer in JavaScript - JavaScriptF1.com
November 2, 2021 - If you want the integer (whole) part of a float without rounding, you can use the Math.trunc function. The Math.trunc() function returns the integer part of a number by removing any fractional digits.
Reddit
reddit.com › r/javascript › [askjs] its about time javascript should get a "integer" and "float" data type.
r/javascript on Reddit: [AskJS] Its about time javascript should get a "integer" and "float" data type.
August 10, 2022 -
After all the improvements/features and fixes which were made to javascript (or precisely ECMAScript) since ES6 (ES2015) till now (ES2022), isn't it about time to fix the ultimate pending weakness i.e. having an Integer and a Float type as well (just like "var" keyword was/is there but they added "let" and "const" as a better semantics and good practice) and not just mashup everything in Number.
Heck, we even got a big int to represent big integers (no floats allowed) but we still don't have Integer's and Floats which are SUPER useful in almost every scenario.
So, why is it still not added and not planned as well? Those are VERY important data types and MOST languages HAVE those data types as they are NEEDED, why is it not planned for ECMAScript? Is it planned? Do you want to see this added?
Top answer 1 of 5
30
JavaScript numbers are double-precision floating-point values, also known as a double in other languages like C. This covers the "float" side of things. Now, a double-precision floating-point value can perfectly represent integers up to 52 bits, which is a lot bigger than the 32 bits an int can typically store in other languages. JavaScript bitwise operators such as & or | or ^ also convert their values to 32-bit integers before doing their work. So, just use regular JavaScript numbers to perform your integer arithmetic, and then throw in a few | 0 operations if you want the rounding / clamping behavior found in other language's 32-bit int types. In other words, everything you want is already present.
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9
Are you actually running into problems with number? Or do you just want it because has it?
Top answer 1 of 7
48
Great Question! I actually had to deal with this the other day! It may seem like a goto to just write parseInt but wait! we can be fancier.
So we can use bit operators for quite a few things and this seems like a great situation! Let's say I have the number from your question, 12.345, I can use the bit operator '~' which inverts all the bits in your number and in the process converts the number to an int! Gotta love JS.
So now we have the inverted bit representation of our number then if we '~' it again we get ........drum roll......... our number without the decimals! Unfortunately, it doesn't do rounding.
var a = 12.345;
var b = ~~a; //boom!
We can use Math.round() for that. But there you go! You can try it on JSperf to see the slight speed up you get! Hope that helps!
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14
this is a good example i think
var intvalue = Math.floor( floatvalue );
var intvalue = Math.ceil( floatvalue );
var intvalue = Math.round( floatvalue );
Google
discuss.google.dev › google cloud › apigee
Float is getting converted to either int or string. But we need to pass it as float. - Apigee - Google Developer forums
April 18, 2024 - We’re using javascript to do it as the response payload consists of lots of arrays. Here there’s a field where we receive it as float and we need to pass a float to source systems. But JS is somehow converting the float to int when decimal part contains only zeros.