diff --git a/hc/front/forms.py b/hc/front/forms.py
index 0783523b..0e1c7363 100644
--- a/hc/front/forms.py
+++ b/hc/front/forms.py
@@ -1,6 +1,5 @@
 from django import forms
 from hc.front.validators import CronExpressionValidator, WebhookValidator
-from hc.api.models import CHECK_KINDS
 
 
 class NameTagsForm(forms.Form):
@@ -19,12 +18,15 @@ class NameTagsForm(forms.Form):
 
 
 class TimeoutForm(forms.Form):
-    kind = forms.ChoiceField(choices=CHECK_KINDS)
     timeout = forms.IntegerField(min_value=60, max_value=2592000)
+    grace = forms.IntegerField(min_value=60, max_value=2592000)
+
+
+class CronForm(forms.Form):
     schedule = forms.CharField(required=False, max_length=100,
                                validators=[CronExpressionValidator()])
     tz = forms.CharField(required=False, max_length=36)
-    grace = forms.IntegerField(min_value=60, max_value=2592000)
+    grace = forms.IntegerField(min_value=1, max_value=43200)
 
 
 class AddPdForm(forms.Form):
diff --git a/hc/front/urls.py b/hc/front/urls.py
index ca9a6f04..88bf9038 100644
--- a/hc/front/urls.py
+++ b/hc/front/urls.py
@@ -32,6 +32,7 @@ urlpatterns = [
     url(r'^$', views.index, name="hc-index"),
     url(r'^checks/$', views.my_checks, name="hc-checks"),
     url(r'^checks/add/$', views.add_check, name="hc-add-check"),
+    url(r'^checks/cron_preview/$', views.cron_preview),
     url(r'^checks/([\w-]+)/', include(check_urls)),
     url(r'^integrations/', include(channel_urls)),
 
diff --git a/hc/front/views.py b/hc/front/views.py
index 50d6c52b..c5dea32a 100644
--- a/hc/front/views.py
+++ b/hc/front/views.py
@@ -1,5 +1,6 @@
 from collections import Counter
-from datetime import timedelta as td
+from croniter import croniter
+from datetime import datetime, timedelta as td
 from itertools import tee
 
 import requests
@@ -12,13 +13,14 @@ from django.shortcuts import get_object_or_404, redirect, render
 from django.urls import reverse
 from django.utils import timezone
 from django.utils.crypto import get_random_string
+from django.views.decorators.csrf import csrf_exempt
 from django.utils.six.moves.urllib.parse import urlencode
 from hc.api.decorators import uuid_or_400
 from hc.api.models import (DEFAULT_GRACE, DEFAULT_TIMEOUT, Channel, Check,
                            Ping, Notification)
 from hc.front.forms import (AddWebhookForm, NameTagsForm,
                             TimeoutForm, AddUrlForm, AddPdForm, AddEmailForm,
-                            AddOpsGenieForm)
+                            AddOpsGenieForm, CronForm)
 from pytz import all_timezones
 
 
@@ -167,22 +169,55 @@ def update_timeout(request, code):
     if check.user != request.team.user:
         return HttpResponseForbidden()
 
-    form = TimeoutForm(request.POST)
-    if form.is_valid():
-        check.kind = form.cleaned_data["kind"]
+    kind = request.POST.get("kind")
+    if kind == "simple":
+        form = TimeoutForm(request.POST)
+        if not form.is_valid():
+            return redirect("hc-checks")
+
+        check.kind = "simple"
         check.timeout = td(seconds=form.cleaned_data["timeout"])
         check.grace = td(seconds=form.cleaned_data["grace"])
+    elif kind == "cron":
+        form = CronForm(request.POST)
+        if not form.is_valid():
+            return redirect("hc-checks")
+
+        check.kind = "cron"
         check.schedule = form.cleaned_data["schedule"]
         check.tz = form.cleaned_data["tz"]
+        check.grace = td(minutes=form.cleaned_data["grace"])
 
-        if check.last_ping:
-            check.alert_after = check.get_alert_after()
-
-        check.save()
+    if check.last_ping:
+        check.alert_after = check.get_alert_after()
 
+    check.save()
     return redirect("hc-checks")
 
 
+@csrf_exempt
+def cron_preview(request):
+    schedule = request.POST.get("schedule")
+    tz = request.POST.get("tz")
+
+    ctx = {
+        "tz": tz,
+        "dates": []
+    }
+
+    try:
+        with timezone.override(tz):
+            now_naive = timezone.make_naive(timezone.now())
+            it = croniter(schedule, now_naive)
+            for i in range(0, 6):
+                date_naive = it.get_next(datetime)
+                ctx["dates"].append(timezone.make_aware(date_naive))
+    except:
+        ctx["error"] = True
+
+    return render(request, "front/cron_preview.html", ctx)
+
+
 @login_required
 @uuid_or_400
 def pause(request, code):
diff --git a/static/css/my_checks.css b/static/css/my_checks.css
index 0dfe3e92..2d1b7c5c 100644
--- a/static/css/my_checks.css
+++ b/static/css/my_checks.css
@@ -1,5 +1,9 @@
-#update-timeout-modal .modal-body {
-    padding-top: 40px;
+#update-timeout-modal .modal-dialog {
+    width: 800px;
+}
+
+#update-timeout-form .modal-body {
+    padding-top: 35px;
 }
 
 .update-timeout-info {
@@ -20,21 +24,59 @@
     width: 100px;
     text-align: left;
     white-space: nowrap;
-
 }
 
-#type-simple, #type-cron {
+.kind-simple, .kind-cron {
     width: 70px;
 }
 
-#schedule-block {
-    margin: 0 50px;
+#update-timeout-simple {
+    display: none;
+}
+
+#update-cron-form .modal-body {
+    padding: 40px;
+}
+
+#update-cron-form label {
+    font-weight: normal;
 }
 
 #tz {
     width: 300px;
 }
 
+#cron-preview {
+    background: #f8f8f8;
+    height: 256px;
+}
+
+#cron-preview p {
+    padding: 8px;
+    font-size: small;
+}
+
+#cron-preview th {
+    border-top: 0;
+    font-weight: normal;
+    font-size: small;
+}
+
+.cron-preview-date {
+    width: 120px;
+}
+
+.cron-preview-rel {
+    font-size: small;
+}
+
+.cron-preview-timestamp {
+    font-size: small;
+    font-family: monospace;
+    text-align: right;
+    color: #888;
+}
+
 #period-slider {
     margin: 20px 50px 80px 50px;
 }
diff --git a/static/js/checks.js b/static/js/checks.js
index 473af3cc..ebd212ac 100644
--- a/static/js/checks.js
+++ b/static/js/checks.js
@@ -1,5 +1,15 @@
 $(function () {
 
+    $(".my-checks-name").click(function() {
+        $("#update-name-form").attr("action", this.dataset.url);
+        $("#update-name-input").val(this.dataset.name);
+        $("#update-tags-input").val(this.dataset.tags);
+        $('#update-name-modal').modal("show");
+        $("#update-name-input").focus();
+
+        return false;
+    });
+
     var MINUTE = {name: "minute", nsecs: 60};
     var HOUR = {name: "hour", nsecs: MINUTE.nsecs * 60};
     var DAY = {name: "day", nsecs: HOUR.nsecs * 24};
@@ -58,7 +68,6 @@ $(function () {
         $("#update-timeout-timeout").val(rounded);
     });
 
-
     var graceSlider = document.getElementById("grace-slider");
     noUiSlider.create(graceSlider, {
         start: [20],
@@ -87,55 +96,73 @@ $(function () {
         $("#update-timeout-grace").val(rounded);
     });
 
+    function showSimple() {
+        console.log("show simple");
+        $("#update-timeout-form").show();
+        $("#update-cron-form").hide();
+    }
 
-    $('[data-toggle="tooltip"]').tooltip();
+    function showCron() {
+        console.log("show cron");
+        $("#update-timeout-form").hide();
+        $("#update-cron-form").show();
+    }
 
-    $(".my-checks-name").click(function() {
-        $("#update-name-form").attr("action", this.dataset.url);
-        $("#update-name-input").val(this.dataset.name);
-        $("#update-tags-input").val(this.dataset.tags);
-        $('#update-name-modal').modal("show");
-        $("#update-name-input").focus();
+    var currentPreviewHash = "";
+    function updateCronPreview() {
+        console.log("requested to update cron preview");
 
-        return false;
-    });
+        var schedule = $("#schedule").val();
+        var tz = $("#tz").val();
+        var hash = schedule + tz;
+
+        // Don't try preview with empty values, or if values have not changed
+        if (!schedule || !tz || hash == currentPreviewHash)
+            return;
+
+        // OK, we're good
+        currentPreviewHash = hash;
+        $("#cron-preview-title").text("Updating...");
+        $.post("/checks/cron_preview/", {schedule: schedule, tz: tz},
+            function(data) {
+                if (hash != currentPreviewHash) {
+                    return;  // ignore stale results
+                }
+
+                $("#cron-preview" ).html(data);
+                var haveError = $("#invalid-cron-expression").size() > 0;
+                $("#update-cron-submit").prop("disabled", haveError);
+            }
+        );
+    }
 
     $(".timeout-grace").click(function() {
         $("#update-timeout-form").attr("action", this.dataset.url);
+        $("#update-cron-form").attr("action", this.dataset.url);
+
+        // Simple
         periodSlider.noUiSlider.set(this.dataset.timeout);
         graceSlider.noUiSlider.set(this.dataset.grace);
+
+        // Cron
+        $("#cron-preview").html("<p>Updating...</p>");
         $("#schedule").val(this.dataset.schedule);
         document.getElementById("tz").selectize.setValue(this.dataset.tz);
+        var minutes = parseInt(this.dataset.grace / 60);
+        $("#update-timeout-grace-cron").val(minutes);
 
-        if (this.dataset.kind == "cron") {
-            $("#type-simple").removeClass("active");
-            $("#type-cron").addClass("active");
-            $("#type-cron input").prop("checked", true);
-
-            $("#period-block").hide();
-            $("#schedule-block").show();
-        } else {
-            $("#type-simple").addClass("active");
-            $("#type-simple input").prop("checked", true);
-            $("#type-cron").removeClass("active");
-
-            $("#period-block").show();
-            $("#schedule-block").hide();
-        }
-
+        this.dataset.kind == "simple" ? showSimple() : showCron();
         $('#update-timeout-modal').modal({"show":true, "backdrop":"static"});
         return false;
     });
 
-    $("#type-simple").click(function() {
-        $("#period-block").show();
-        $("#schedule-block").hide();
-    });
+    // Wire up events for Timeout/Cron forms
+    $(".kind-simple").click(showSimple);
+    $(".kind-cron").click(showCron);
+
+    $("#schedule").on("keyup", updateCronPreview);
+    $("#tz").on("change", updateCronPreview);
 
-    $("#type-cron").click(function() {
-        $("#period-block").hide();
-        $("#schedule-block").show();
-    });
 
     $(".check-menu-remove").click(function() {
         $("#remove-check-form").attr("action", this.dataset.url);
@@ -189,6 +216,8 @@ $(function () {
         return false;
     });
 
+    $('[data-toggle="tooltip"]').tooltip();
+    $("#tz").selectize();
 
     $(".usage-examples").click(function(e) {
         var a = e.target;
@@ -202,8 +231,6 @@ $(function () {
         return false;
     });
 
-    $("#tz").selectize();
-
     var clipboard = new Clipboard('button.copy-link');
     $("button.copy-link").mouseout(function(e) {
         setTimeout(function() {
diff --git a/templates/front/cron_preview.html b/templates/front/cron_preview.html
new file mode 100644
index 00000000..60b2e1bb
--- /dev/null
+++ b/templates/front/cron_preview.html
@@ -0,0 +1,20 @@
+{% load humanize tz %}
+
+{% if error %}
+<p id="invalid-cron-expression">Invalid cron expression</p>
+{% else %}
+<table class="table">
+    <tr>
+        <th id="cron-preview-title" colspan="3">Expected Ping Dates</th>
+    </tr>
+    {% for date in dates %}
+    <tr>
+        {% timezone tz %}
+        <td class="cron-preview-date">{{ date|date:"M j, H:i" }}</td>
+        {% endtimezone %}
+        <td class="cron-preview-rel">{{ date|naturaltime }}</td>
+        <td class="cron-preview-timestamp">{{ date|date:"c" }}</td>
+    </tr>
+    {% endfor %}
+</table>
+{% endif %}
\ No newline at end of file
diff --git a/templates/front/my_checks.html b/templates/front/my_checks.html
index d24153c2..da74e2b2 100644
--- a/templates/front/my_checks.html
+++ b/templates/front/my_checks.html
@@ -110,52 +110,30 @@
 
 <div id="update-timeout-modal" class="modal">
     <div class="modal-dialog">
-        <form id="update-timeout-form" method="post">
-            {% csrf_token %}
-            <input type="hidden" name="timeout" id="update-timeout-timeout" />
-            <input type="hidden" name="grace" id="update-timeout-grace" />
-            <div class="modal-content">
+        <div class="modal-content">
+            <form id="update-timeout-form" method="post">
+                {% csrf_token %}
+                <input type="hidden" name="kind" value="simple" />
+                <input type="hidden" name="timeout" id="update-timeout-timeout" />
+                <input type="hidden" name="grace" id="update-timeout-grace" />
+
                 <div class="modal-body">
-                    <div id="period-block">
-                        <div class="update-timeout-info text-center">
-                            <span
-                                class="update-timeout-label"
-                                data-toggle="tooltip"
-                                title="Expected time between pings.">
-                                Period
-                            </span>
-                            <span
-                                id="period-slider-value"
-                                class="update-timeout-value">
-                                1 day
-                            </span>
-                        </div>
-                        <div id="period-slider"></div>
-                    </div>
-                    <div id="schedule-block">
-                        <div class="form-group">
-                            <label for="schedule">
-                                Cron expression
-                                <a href="https://en.wikipedia.org/wiki/Cron#Overview">(reference)</a>
-                            </label>
-                            <input
-                                type="text"
-                                class="form-control input-lg"
-                                id="schedule"
-                                name="schedule"
-                                placeholder="* * * * *">
-                        </div>
-                        <div class="form-group">
-                            <label for="schedule">Server's Timezone</label>
-                            <br />
-                            <select id="tz" name="tz" class="form-control">
-                                <option>UTC</option>
-                                {% for tz in timezones %}
-                                <option>{{ tz }}</option>{% endfor %}
-                            </select>
-                        </div>
+                    <div class="update-timeout-info text-center">
+                        <span
+                            class="update-timeout-label"
+                            data-toggle="tooltip"
+                            title="Expected time between pings.">
+                            Period
+                        </span>
+                        <span
+                            id="period-slider-value"
+                            class="update-timeout-value">
+                            1 day
+                        </span>
                     </div>
 
+                    <div id="period-slider"></div>
+
                     <div class="update-timeout-info text-center">
                         <span
                             class="update-timeout-label"
@@ -182,25 +160,82 @@
                             When a check is late, how much time to wait until alert is sent.
                         </p>
                     </div>
-
                 </div>
+
                 <div class="modal-footer">
-                    <div class="btn-group pull-left" data-toggle="buttons">
-                        <label id="type-simple" class="btn btn-default">
-                            <input type="radio" name="kind" value="simple" autocomplete="off">
-                            Simple
-                        </label>
-                        <label id="type-cron" class="btn btn-default">
-                            <input type="radio" name="kind" value="cron" autocomplete="off">
-                            Cron
-                        </label>
+                    <div class="btn-group pull-left">
+                        <label class="btn btn-default kind-simple active">Simple</label>
+                        <label class="btn btn-default kind-cron">Cron</label>
                     </div>
 
                     <button type="button" class="btn btn-default" data-dismiss="modal">Cancel</button>
                     <button type="submit" class="btn btn-primary">Save</button>
                 </div>
-            </div>
-        </form>
+            </form>
+
+            <form id="update-cron-form" method="post">
+                {% csrf_token %}
+                <input type="hidden" name="kind" value="cron" />
+                <div class="modal-body">
+                    <div class="row">
+                        <div class="col-sm-4">
+                            <div class="form-group">
+                                <label for="schedule">Cron Expression</label>
+                                <input
+                                    type="text"
+                                    class="form-control"
+                                    id="schedule"
+                                    name="schedule"
+                                    placeholder="* * * * *">
+                            </div>
+                        </div>
+                        <div class="col-sm-4">
+                            <div class="form-group">
+                                <label for="tz">Server's Timezone</label>
+                                <br />
+                                <select id="tz" name="tz" class="form-control">
+                                    <option>UTC</option>
+                                    {% for tz in timezones %}
+                                    <option>{{ tz }}</option>{% endfor %}
+                                </select>
+                            </div>
+                        </div>
+                        <div class="col-sm-4">
+                            <div class="form-group">
+                                <label for="cron-grace">Grace Time</label>
+                                <div class="input-group">
+                                    <input
+                                        type="number"
+                                        min="1"
+                                        max="43200"
+                                        class="form-control"
+                                        id="update-timeout-grace-cron"
+                                        name="grace">
+                                    <div class="input-group-addon">minutes</div>
+                                </div>
+                            </div>
+                        </div>
+                    </div>
+                    <div class="row">
+                        <div class="col-sm-12">
+                            <div id="cron-preview"></div>
+                        </div>
+                    </div>
+                </div>
+
+                <div class="modal-footer">
+                    <div class="btn-group pull-left">
+                        <label class="btn btn-default kind-simple">Simple</label>
+                        <label class="btn btn-default active kind-cron">Cron</label>
+                    </div>
+
+                    <button type="button" class="btn btn-default" data-dismiss="modal">Cancel</button>
+                    <button id="update-cron-submit" type="submit" class="btn btn-primary">
+                        Save
+                    </button>
+                </div>
+            </form>
+        </div>
     </div>
 </div>