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Number input type that takes only integers?

I'm using the jQuery Tools Validator which implements HTML5 validations through jQuery.

It's been working great so far except for one thing. In the HTML5 specification, the input type "number" can have both integers and floating-point numbers.

This seems incredibly short-sighted since it will only be a useful validator when your database fields are signed floating-point numbers (for unsigned ints you'll have to fall back to pattern validation and thus lose extra features like the up and down arrows for browsers that support it).

Is there another input type or perhaps an attribute that would restrict the input to just unsigned integers?

I couldn't find any.

Setting the step to 1 is not the answer since it doesn't restrict the input. You can still type a negative floating-point number into the textbox.

Also, I am aware of pattern validation (I mentioned it in my original post), but that was not part of the question.

I wanted to know if HTML5 allowed restricting an input of type "number" to positive integer values. To this question the answer, it seems, would be "no, it does not".

I didn't want to use pattern validation because this causes some drawbacks when using jQuery Tools validation, but it now seems that the specification doesn't allow for a cleaner way to do this.

As of 2019—I don't know since when—the number input (in FF/Chrome/Safari at least) now only accepts integers by default, unless you set an explicit value for the step attr that allows decimal values; e.g: step="0.01". Documented MDN here. In two minds about this because I think it's a sensible default, but also a breaking change (yes, it has affected some code I wrote).
@DarraghEnright Chrome 87 allows non integers to be entered when step="1". MDN says the behavior is up to the browser.

M
Mmmh mmh

The best you can achieve with HTML only (documentation):


You should probably set min to 1 as he wants positive numbers (and not non-negative numbers).
This did not worked for me on latest version of chrome. It does not allow letters to be typed, but it does allow special characters to be inserted.
Why I can type e in
@grantsun for exponential numbers e.g. 10e20.
This is not right if you want to "restrict the input to just unsigned integers". The "step" attribute will control the increment/decrement of the input value using the keyboard arrows. It will not prevent decimal input values.
e
enzo

Set the step attribute to 1:

This seems a bit buggy in Chrome right now so it might not be the best solution at the moment.

A better solution is to use the pattern attribute, that uses a regular expression to match the input:

\d is the regular expression for a number, * means that it accepts more than one of them.


As JayPea learned, not all browsers support all HTML5 elements yet, so it's best to provide graceful degrading, as you have proposed.
@Zut HTML5 validation doesn't stop you from entering those keys. It just prevents the form from being send with those characters. If you submit a form with an input of the type number that contains other characters, then Chrome will show you an error message.
@dotweb - I see your point. The difference between the two is that with the number attribute, all alphabetic characters are automatically removed when I deselect (trigger blur) for the input. This does not happen when using the pattern attribute. I guess this distinction is only important if you are using AJAX to post your data, and you're using some other event than submit to trigger the post.
This does not do what OP asked. Only integers /\d*/.test(1.1) // true
@vsync pattern="\d*" is not the same as /\d*/, pattern="\d*" is equal to /^(?:\d*)$/, please refer to HTML5 pattern attribute documentation.
T
Tarek Kalaji

The easy way using JavaScript:

<input type="text" oninput="this.value = this.value.replace(/[^0-9.]/g, ''); this.value = this.value.replace(/(\..*)\./g, '$1');" >

I dont understand replace(/(\..*)\./g, '$1')
This is important to accept float numbers and repeat . only once, e.g. 123.556 can be writen.
@TarekKalaji - questions states integers and not float numbers
how about mobile device? because type text display all keyboards (alfanumeric chars also)
M
Mister Jojo
<input type="text" name="PhoneNumber" pattern="[0-9]{10}" title="Phone number">

Using this code, the input to the text field limits to enter only digits. Pattern is the new attribute available in HTML 5.

Pattern attribute doc


According to the specification the pattern attribute can only be used where the input type is Text, Search, URL, Telephone, E-mail, Password (as shown here with the "Text" type). This means that semantics of the number input type and therefore (importantly) the numeric on-screen keyboards of some tablets and phones is lost when using this method.
This on firefox 36.0 allows you to type letters and special characters.
It doesn't limit input to numbers only, you can still type letters!
V
Viktor Karpyuk

Pattern is nice but if you want to restrict the input to numbers only with type="text", you can use oninput and a regex as below:

<input type="text" oninput="this.value=this.value.replace(/[^0-9]/g,'');" id="myId"/>

I warks for me :)


Beware that this approach might negate your (change) method (event handler) and also erase your default value in the input box.
R
R. Yaghoobi


Bro, this solution is key! Thank you!
The best solution.
2
2 revs, 2 users 60%

This is not only for html5 all browser is working fine . try this

onkeyup="this.value=this.value.replace(/[^0-9]/g,'');"

This is bad. On the input try: Shift+Home, Shift+End, Ctrl+A, Ctrl+C, Ctrl+V. Use oninput instead
When this answer was written, HTML5 was not published. @zanderwar
I try just now and IT WORKS! Thank You.
d
dippas

Pattern are always preferable for restriction, try oninput and min occur 1 for inputting only numbers from 1 onwards

<input type="text" min="1" oninput="this.value=this.value.replace(/[^0-9]/g,'');"
                                value=${var} >

It is very instresting solution. What for ` value=${var}` is?
@AcademyofProgrammer example default value for that input
best answer! works for pasting, works even in IE (10+), gives you the freedom to display any keyboard via the input's type, and does not make chrome display these pesky up/down arrows inside the field.
This solution will reset the whole input when user entered one wrong char.. The solution is cool indeed, but not so user friendly
K
Kamil Kiełczewski

Shortest

This is size improvement of R. Yaghoobi answer

We use here standard shorthand for "OR" operator e.g 9 | 2 = 11 in binary: 0b1001 | 0b1010 = 0b1011 . This operator first cast numbers to integers in implicit way and then do OR. But because OR with zero don't change anything so number is cast to integer. OR with non-number string gives 0.


Kielczewski Which operator is this?
Outstanding! Good job! Thanks!
This is by far the best answer. Not only deals with the problem in a short, simple way; it also deals with localization issues (e.g. 100,5 vs 100.5 depending on what country you're from) which most other answers don't.
you can add a dot
i
illeas

Just putting it in your input field : onkeypress='return event.charCode >= 48 && event.charCode <= 57'


Maybe you have other problems.
No. Your proposal does not handle case when I just paste value to the field. It handles only case when I enter value digit by digit.
a
a.valchev

I was working oh Chrome and had some problems, even though I use html attributes. I ended up with this js code

$("#element").on("input", function(){
        var value = $(this).val();

        $(this).val("");
        $(this).val(parseInt(value));

        return true;
});

I ended up using this as well with 1 minor tweak; I changed parseInt(value) to parseInt(value.replace('.', ''). This allowed me to paste 1.56 and keep the displayed value at 156 instead of 1.
d
dippas

Set step attribute to any float number, e.g. 0.01 and you are good to go.


d
dippas

have you tried setting the step attribute to 1 like this

<input type="number" step="1" /> 

L
Luca Fagioli

Maybe it does not fit every use case, but

<input type="range" min="0" max="10" />

can do a fine job: fiddle.

Check the documentation.


@ViacheslavDobromyslov Not sure what you are looking for, but I remind you the OP question: "Is there another input type or perhaps an attribute that would restrict the input to just unsigned integers?" Why do you sentence this answer as "not working", if it does exactly what the OP asked?
Because it's near to impossible to input a value from ~9 quadrillion integers using the proposed range input control.
@ViacheslavDobromyslov Where this 9 quadrillions requirement come from? The OP didn't ask about that. This answer replies the OP question, no what you have in mind.
He has not asked for a solution with 10 numbers in a row. Your solution does not work for any range.
@ViacheslavDobromyslov It does a good job especially with short ranges. Give it a try, I'm sure it would fit well your necessities.
d
deltragon

This is an old question, but the accessible (and now supported in most browsers) version would be:

<input type="text" inputmode="numeric" pattern="[0-9]*">

See https://technology.blog.gov.uk/2020/02/24/why-the-gov-uk-design-system-team-changed-the-input-type-for-numbers/


The pattern you have used only allows integers between 0 and 9. It doesn't allow negatives or values greater than 9
@Ted The * in the pattern means 0 or more repetitions, meaning eg. 10 or 2134 are also allowed. Additionally, the question specifically asks for unsigned numbers, ie. no negatives - if you want to allow negative numbers the pattern would be pattern="-?[0-9]*".
that might be, but it still didn't work correctly when using validators. It wouldn't allow values greater than 9. I replaced the pattern with pattern="\d*" and it now works fine
V
Valentin Despa

Yes, HTML5 does. Try this code (w3school):

<!DOCTYPE html>
<html>
<body>

<form action="">
  Quantity (between 1 and 5): <input type="number" name="quantity" min="1" max="5" />
  <input type="submit" />
</form>

</body>
</html>

See the min and max paremeter? I tried it using Chrome 19 (worked) and Firefox 12 (did not work).


This assumes that you want a known range. But if you wanted any integer value, would this still work?
E
Eric Aya

Currently, it is not possible to prevent a user from writing decimal values in your input with HTML only. You have to use javascript.


S
Sarthak
var valKeyDown;
var valKeyUp;


function integerOnly(e) {
    e = e || window.event;
    var code = e.which || e.keyCode;
    if (!e.ctrlKey) {
        var arrIntCodes1 = new Array(96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 8, 9, 116);   // 96 TO 105 - 0 TO 9 (Numpad)
        if (!e.shiftKey) {                          //48 to 57 - 0 to 9 
            arrIntCodes1.push(48);                  //These keys will be allowed only if shift key is NOT pressed
            arrIntCodes1.push(49);                  //Because, with shift key (48 to 57) events will print chars like @,#,$,%,^, etc.
            arrIntCodes1.push(50);
            arrIntCodes1.push(51);
            arrIntCodes1.push(52);
            arrIntCodes1.push(53);
            arrIntCodes1.push(54);
            arrIntCodes1.push(55);
            arrIntCodes1.push(56);
            arrIntCodes1.push(57);
        }
        var arrIntCodes2 = new Array(35, 36, 37, 38, 39, 40, 46);
        if ($.inArray(e.keyCode, arrIntCodes2) != -1) {
            arrIntCodes1.push(e.keyCode);
        }
        if ($.inArray(code, arrIntCodes1) == -1) {
            return false;
        }
    }
    return true;
}

$('.integerOnly').keydown(function (event) {
    valKeyDown = this.value;
    return integerOnly(event);
});

$('.integerOnly').keyup(function (event) {          //This is to protect if user copy-pastes some character value ,..
    valKeyUp = this.value;                          //In that case, pasted text is replaced with old value,
    if (!new RegExp('^[0-9]*$').test(valKeyUp)) {   //which is stored in 'valKeyDown' at keydown event.
        $(this).val(valKeyDown);                    //It is not possible to check this inside 'integerOnly' function as,
    }                                               //one cannot get the text printed by keydown event 
});                                                 //(that's why, this is checked on keyup)

$('.integerOnly').bind('input propertychange', function(e) {    //if user copy-pastes some character value using mouse
    valKeyUp = this.value;
    if (!new RegExp('^[0-9]*$').test(valKeyUp)) {
        $(this).val(valKeyDown);
    }
});

d
dippas

From the specs

step="any" or positive floating-point number Specifies the value granularity of the element’s value.

So you could simply set it to 1:


I've tried this but the problem is that you can still type a floating point number in the text box.
So, you need code that blocks the user from typing a decimal point?
N
Nitish Jha

Posting it, if anyone requires it in future

const negativeValuePrevent = (e) => {
    const charCode = e.which ? e.which : e.keyCode;
    if(charCode > 31 && (charCode < 48 || charCode > 57) 
    && charCode !== 46){
      if(charCode < 96 || charCode > 105){
        e.preventDefault();
        return false;
      }
    }
    return true;
  };

T
Ted

Most of the answers are outdated.

The following does not work anymore:

<!-- It doesn't invalidate decimals when using validators -->
<input type="number" min="0" step="1" />

The below solution is much more elegant and straight-forward and works on all latest browsers as of early 2022.

<!-- It DOES invalidate decimals when using validators -->
<input type="number" pattern="\d*" />

K
Kamil Kiełczewski

Short and user friendly

This solution supports tab, backspace, enter, minus in intuitive way

however it not allow to change already typed number to minus and not handle copy-paste case.

As alternative you can use solution based on R. Yaghoobi answer which allow to put minus and handle copy-paste case, but it delete whole number when user type forbidden character


F
Farhan

The integer input would mean that it can only take positive numbers, 0 and negative numbers too. This is how I have been able to achieve this using Javascript keypress.

<input type="number" (keypress)="keypress($event, $event.target.value)" >

keypress(evt, value){
  
    if (evt.charCode >= 48 && evt.charCode <= 57 || (value=="" && evt.charCode == 45))       
    {  
      return true;
    }
    return false;
}

The given code won't allow user to enter alphabets nor decimal on runtime, just positive and negative integer values.


w
weston

In the Future™ (see Can I Use), on user agents that present a keyboard to you, you can restrict a text input to just numeric with input[inputmode].


inputmode is mostly for hand-held devices and will trigger the correct keyboard layout, but for "normal" computers with keyboards, it iwll not prevent entering whatever you want.