ISO - ISO 8601 — Date and time format

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">Popular standards</a></div> <h1>ISO 8601</h1> <h2 class="mt-0 ">Date and time format</h2></nav></div></div> </div> </section><section id="highlight-section" class="mt-0 bg-lightgray"> <div class="container"> <div class="row row-title " > <div class="col-md-12"></div></div><div class="row " > <div class="col-md-7"><p class="lead">Looking for an unambiguous calendar-and-clock format that is internationally understood? It’s time for ISO 8601.</p> <p>This ISO standard helps remove doubts that can result from the various day–date conventions, cultures and time zones that impact a global operation. It gives a way of presenting dates and times that is clearly defined and understandable to both people and machines.</p></div> <div class="col-md-4 col-md-offset-1"></div></div></div> </section> <svg class="wave" preserveAspectRatio="none" aria-hidden="true" focusable="false" viewBox="0 0 1440 96" fill="none" xmlns="http://www.w3.org/2000/svg"><path d="m0 96 80-5C160 85 320 75 480 64s320-21 480-21c160 0 320 10 400 16l80 5V0H0v96Z"></path></svg><section id="main-section" class=" "> <div class="container"> <div class="row row-title " > <div class="col-md-12"></div></div><div class="row " > <div class="col-md-7"><h3>What can ISO 8601 do for me?</h3> <p>When dates are represented with numbers they can be interpreted in different ways. For example, 01/05/22 could mean January 5, 2022, or May 1, 2022. On an individual level this uncertainty can be very frustrating, in a business context it can be very expensive. Organizing meetings and deliveries, writing contracts and buying airplane tickets can be very difficult when the date is unclear.</p> <p>ISO 8601 tackles this uncertainty by setting out an internationally agreed way to represent dates:</p> <p>YYYY-MM-DD</p> <p>Therefore, the order of the elements used to express date and time in ISO 8601 is as follows: year, month, day, hour, minutes, seconds, and milliseconds.</p> <p>For example, September 27, 2022 at 6 p.m. is represented as 2022-09-27 18:00:00.000.</p><p>ISO 8601 can be used by anyone who wants to use a standardized way of presenting:</p> <ul> <li>Date</li> <li>Time of day</li> <li>Coordinated Universal Time (UTC)</li> <li>Local time with offset to UTC</li> <li>Date and time</li> <li>Time intervals</li> <li>Recurring time intervals</li> </ul></div> <div class="col-md-4 col-md-offset-1"><div class="media clearfix square"> <div class="media-left"> <figure class=""> <a href="/news/2017/02/Ref2164.html" title="Date and time: the new draft of ISO 8601 explained by Klaus-Dieter Naujok" aria-label="Date and time: the new draft of ISO 8601 explained by Klaus-Dieter Naujok"><img loading="lazy" src="/files/live/sites/isoorg/files/archive/Ref2164/img_ref2164_01.jpg/thumbnails/150x150" srcset="/files/live/sites/isoorg/files/archive/Ref2164/img_ref2164_01.jpg/thumbnails/150x150 150w, /files/live/sites/isoorg/files/archive/Ref2164/img_ref2164_01.jpg/thumbnails/300x300 300w" sizes="100px" class="img-fluid hover-zoom" alt="" /> </a></figure> </div> <div class="media-body"> <div class="entry-description small text-muted"> <span class="time text-muted"> <time class='updated' datetime='2017-02-21'>21 February 2017</time> </span> </div> <div class="entry-header"> <div class="h5"> <a href="/news/2017/02/Ref2164.html" title="" ><span class="entry-name">Date and time: the new draft of ISO 8601 explained by Klaus-Dieter Naujok</span></a></div> <div class="entry-summary"> Standardization is a truly international activity, and I’ve been lucky to have worked with more nationalities than I can remember. But, that said, my first business meeting with a German remains etched …</div> </div> </div> </div></div></div></div> </section><section class=" bg-danger"> <div class="container"> <div class="row " > <div class="col-md-4"><h2>Highlights from our store</h2></div> <div class="col-md-7 col-md-offset-1"><ul class="refine"><li><div class="clearfix"> <div class="h4"> <a href="/standard/70907.html"><span class="entry-name">ISO 8601-1:2019</span></a><div class="entry-title">Date and time</div></div> <div class="entry-description">Representations for information interchange – Part 1: Basic rules</div> </div></li><li><div class="clearfix"> <div class="h4"> <a href="/standard/70908.html"><span class="entry-name">ISO 8601-2:2019</span></a><div class="entry-title">Date and time</div></div> <div class="entry-description">Representations for information interchange – Part 2: Extensions</div> </div></li></ul></div></div> </div> </section><div class="nav-breadcrumb print-footer bg-black"> <div class="container"> <div class="row"> <div class="col-sm-10 small">  <ol class="breadcrumb"> <li class="breadcrumb-item"><a href="/home.html" title="Home page"><i class="bi-house" aria-hidden="true"></i></a></li> <li class="breadcrumb-item"> <a href="/standards.html">Standards</a> </li> <li class="breadcrumb-item"> <a href="/popular-standards.html">Popular standards</a> </li> <li class="breadcrumb-item"> ISO 8601 — Date and time format</li> </ol></div> <div class="col-sm-2 hidden-print text-end small mt-3 mt-sm-0"> <a role="button" class="dropdown-toggle text-white collapsed" data-bs-toggle="collapse" href="#collapseSitemap" target="_self" aria-expanded="false" aria-controls="collapseSitemap">Sitemap</a> </div> </div> <div class="collapse border-top" id="collapseSitemap"> <div class="row">  <nav role="navigation" aria-label="Sitemap" class="sitemap-footer clearfix small" id="nav-sitemap"><ul role='menubar' class='list-inline-5 clearfix nav-level1' ><li role='menuitem' class=' hasChildren inPath firstInLevel' ><a class='nav-link ' title="Covering almost every product, process or service imaginable, ISO makes standards used everywhere." href='/standards.html'>Standards</a><ul role='menubar' class='list-unstyled nav-level2' ><li role='menuitem' class=' noChildren firstInLevel' ><a class='nav-link ' title="Whether you run a business, work for a company or government, or you are a consumer looking for goods and services that meet customer expectations: Find out what standards can do for you." href='/benefits-of-standards.html'>Benefits</a></li><li role='menuitem' class=' noChildren inPath ' ><a class='nav-link ' title="Here you can discover some of the best-known and most widely-used standards, as well as those that address recently emerged challenges affecting us all. 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remove_tooltip(elem) : false; if (elem.type != 'checkbox') elem.className = elem.className.replace(/ ?_has_error ?/g, ''); if (elem.getAttribute('required') !== null) { if (elem.type == 'radio' || (elem.type == 'checkbox' && /any/.test(elem.className))) { var elems = form_to_submit.elements[elem.name]; if (!(elems instanceof NodeList || elems instanceof HTMLCollection) || elems.length <= 1) { no_error = elem.checked; } else { no_error = false; for (var i = 0; i < elems.length; i++) { if (elems[i].checked) no_error = true; } } if (!no_error) { tooltip = create_tooltip(elem, "Please select an option."); } } else if (elem.type =='checkbox') { var elems = form_to_submit.elements[elem.name], found = false, err = []; no_error = true; for (var i = 0; i < elems.length; i++) { if (elems[i].getAttribute('required') === null) continue; if (!found && elems[i] !== elem) return true; found = true; elems[i].className = elems[i].className.replace(/ ?_has_error ?/g, ''); if (!elems[i].checked) { no_error = false; elems[i].className = elems[i].className + ' _has_error'; err.push("Checking %s is required".replace("%s", elems[i].value)); } } if (!no_error) { tooltip = create_tooltip(elem, err.join('<br/>')); } } else if (elem.tagName == 'SELECT') { var selected = true; if (elem.multiple) { selected = false; for (var i = 0; i < elem.options.length; i++) { if (elem.options[i].selected) { selected = true; break; } } } else { for (var i = 0; i < elem.options.length; i++) { if (elem.options[i].selected && (!elem.options[i].value || (elem.options[i].value.match(/\n/g)))) { selected = false; } } } if (!selected) { elem.className = elem.className + ' _has_error'; no_error = false; tooltip = create_tooltip(elem, "Please select an option."); } } else if (value === undefined || value === null || value === '') { elem.className = elem.className + ' _has_error'; no_error = false; tooltip = create_tooltip(elem, "This field is required"); } } if (no_error && (elem.id == 'field[]' || elem.id == 'ca[11][v]')) { if (elem.className.includes('phone-input-error')) { elem.className = elem.className + ' _has_error'; no_error = false; } } if (no_error && elem.name == 'email') { if (!value.match(/^[\+_a-z0-9-'&=]+(\.[\+_a-z0-9-']+)*@[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,})$/i)) { elem.className = elem.className + ' _has_error'; no_error = false; tooltip = create_tooltip(elem, 'Please enter a valid email address'); } } if (no_error && /date_field/.test(elem.className)) { if (!value.match(/^\d\d\d\d-\d\d-\d\d$/)) { elem.className = elem.className + ' _has_error'; no_error = false; tooltip = create_tooltip(elem, "Enter a valid date."); } } tooltip ? resize_tooltip(tooltip) : false; return no_error; }; var needs_validate = function(el) { if(el.getAttribute('required') !== null){ return true } if(el.name === 'email' && el.value !== ""){ return true } if((el.id == 'field[]' || el.id == 'ca[11][v]') && el.className.includes('phone-input-error')){ return true } return false }; var validate_form = function(e) { var err = form_to_submit.querySelector('._form_error'), no_error = true; if (!submitted) { submitted = true; for (var i = 0, len = allInputs.length; i < len; i++) { var input = allInputs[i]; if (needs_validate(input)) { if (input.type == 'tel') { addEvent(input, 'blur', function() { this.value = this.value.trim(); validate_field(this, true); }); } if (input.type == 'text' || input.type == 'number' || input.type == 'time') { addEvent(input, 'blur', function() { this.value = this.value.trim(); validate_field(this, true); }); addEvent(input, 'input', function() { validate_field(this, true); }); } else if (input.type == 'radio' || input.type == 'checkbox') { (function(el) { var radios = form_to_submit.elements[el.name]; for (var i = 0; i < radios.length; i++) { addEvent(radios[i], 'click', function() { validate_field(el, true); }); } })(input); } else if (input.tagName == 'SELECT') { addEvent(input, 'change', function() { validate_field(this, true); }); } else if (input.type == 'textarea'){ addEvent(input, 'input', function() { validate_field(this, true); }); } } } } remove_tooltips(); for (var i = 0, len = allInputs.length; i < len; i++) { var elem = allInputs[i]; if (needs_validate(elem)) { if (elem.tagName.toLowerCase() !== "select") { elem.value = elem.value.trim(); } validate_field(elem) ? true : no_error = false; } } if (!no_error && e) { e.preventDefault(); } resize_tooltips(); return no_error; }; addEvent(window, 'resize', resize_tooltips); addEvent(window, 'scroll', resize_tooltips); var hidePhoneInputError = function(inputId) { var errorMessage = document.getElementById("error-msg-" + inputId); var input = document.getElementById(inputId); errorMessage.classList.remove("phone-error"); errorMessage.classList.add("phone-error-hidden"); input.classList.remove("phone-input-error"); }; var initializePhoneInput = function(input, defaultCountry) { return window.intlTelInput(input, { utilsScript: "https://unpkg.com/intl-tel-input@17.0.18/build/js/utils.js", autoHideDialCode: false, separateDialCode: true, initialCountry: defaultCountry, preferredCountries: [] }); } var setPhoneInputEventListeners = function(inputId, input, iti) { input.addEventListener('blur', function() { var errorMessage = document.getElementById("error-msg-" + inputId); if (input.value.trim()) { if (iti.isValidNumber()) { iti.setNumber(iti.getNumber()); if (errorMessage.classList.contains("phone-error")){ hidePhoneInputError(inputId); } } else { showPhoneInputError(inputId) } } else { if (errorMessage.classList.contains("phone-error")){ hidePhoneInputError(inputId); } } }); input.addEventListener("countrychange", function() { iti.setNumber(''); }); input.addEventListener("keydown", function(e) { var charCode = (e.which) ? e.which : e.keyCode; if (charCode > 31 && (charCode < 48 || charCode > 57) && charCode !== 8) { e.preventDefault(); } }); }; var showPhoneInputError = function(inputId) { var errorMessage = document.getElementById("error-msg-" + inputId); var input = document.getElementById(inputId); errorMessage.classList.add("phone-error"); errorMessage.classList.remove("phone-error-hidden"); input.classList.add("phone-input-error"); }; var form_submit = function(e) { e.preventDefault(); if (validate_form()) { // use this trick to get the submit button & disable it using plain javascript document.querySelector('#_form_23_submit').disabled = true; var _form_serialize_23 = function(form){if(!form||form.nodeName!=="FORM"){return }var i,j,q=[];for(i=0;i<form.elements.length;i++){if(form.elements[i].name===""){continue}switch(form.elements[i].nodeName){case"INPUT":switch(form.elements[i].type){case"tel":q.push(form.elements[i].name+"="+encodeURIComponent(form.elements[i].previousSibling.querySelector('div.iti__selected-dial-code').innerText)+encodeURIComponent(" ")+encodeURIComponent(form.elements[i].value));break;case"text":case"number":case"date":case"time":case"hidden":case"password":case"button":case"reset":case"submit":q.push(form.elements[i].name+"="+encodeURIComponent(form.elements[i].value));break;case"checkbox":case"radio":if(form.elements[i].checked){q.push(form.elements[i].name+"="+encodeURIComponent(form.elements[i].value))}break;case"file":break}break;case"TEXTAREA":q.push(form.elements[i].name+"="+encodeURIComponent(form.elements[i].value));break;case"SELECT":switch(form.elements[i].type){case"select-one":q.push(form.elements[i].name+"="+encodeURIComponent(form.elements[i].value));break;case"select-multiple":for(j=0;j<form.elements[i].options.length;j++){if(form.elements[i].options[j].selected){q.push(form.elements[i].name+"="+encodeURIComponent(form.elements[i].options[j].value))}}break}break;case"BUTTON":switch(form.elements[i].type){case"reset":case"submit":case"button":q.push(form.elements[i].name+"="+encodeURIComponent(form.elements[i].value));break}break}}return q.join("&")}; let serialized_23 = _form_serialize_23(document.getElementById('_form_23_')).replace(/%0A/g, '\\n'); var err = form_to_submit.querySelector('._form_error'); err ? 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ISO - ISO 8601 — Date and time format