diff --git a/src/sentry/api/utils.py b/src/sentry/api/utils.py
index 33b9cbd6c1339d..25ca63b7235fcd 100644
--- a/src/sentry/api/utils.py
+++ b/src/sentry/api/utils.py
@@ -9,19 +9,36 @@
 
 MIN_STATS_PERIOD = timedelta(hours=1)
 MAX_STATS_PERIOD = timedelta(days=90)
+# make sure to update this message if you are changing the min/max period
+INVALID_PERIOD_ERROR = 'Time window must be greater than an hour and less than or equal to 90 days'
 
 
 class InvalidParams(Exception):
     pass
 
 
+def get_datetime_from_stats_period(stats_period, now=None):
+    if now is None:
+        now = timezone.now()
+    stats_period = parse_stats_period(stats_period)
+    if stats_period is None:
+        raise InvalidParams('Invalid statsPeriod')
+    return now - stats_period
+
+
 def get_date_range_from_params(params, optional=False):
     """
     Gets a date range from standard date range params we pass to the api.
+
     If `statsPeriod` is passed then convert to a time delta and make sure it
     fits within our min/max period length. Values are in the format
     <number><period_type>, where period type is one of `s` (seconds),
     `m` (minutes), `h` (hours) or `d` (days).
+
+    Similarly, `statsPeriodStart` and `statsPeriodEnd` allow for selecting a
+    relative range, for example: 15 days ago through 8 days ago. This uses the same
+    format as `statsPeriod`
+
     :param params:
     If `start` end `end` are passed, validate them, convert to `datetime` and
     returns them if valid.
@@ -35,11 +52,18 @@ def get_date_range_from_params(params, optional=False):
     start = now - MAX_STATS_PERIOD
 
     stats_period = params.get('statsPeriod')
+    stats_period_start = params.get('statsPeriodStart')
+    stats_period_end = params.get('statsPeriodEnd')
+
     if stats_period is not None:
-        stats_period = parse_stats_period(stats_period)
-        if stats_period is None or stats_period < MIN_STATS_PERIOD or stats_period >= MAX_STATS_PERIOD:
-            raise InvalidParams('Invalid statsPeriod')
-        start = now - stats_period
+        start = get_datetime_from_stats_period(stats_period, now)
+
+    elif stats_period_start or stats_period_end:
+        if not all([stats_period_start, stats_period_end]):
+            raise InvalidParams('statsPeriodStart and statsPeriodEnd are both required')
+        start = get_datetime_from_stats_period(stats_period_start, now)
+        end = get_datetime_from_stats_period(stats_period_end, now)
+
     elif params.get('start') or params.get('end'):
         if not all([params.get('start'), params.get('end')]):
             raise InvalidParams('start and end are both required')
@@ -48,9 +72,14 @@ def get_date_range_from_params(params, optional=False):
             end = parse_datetime_string(params['end'])
         except InvalidQuery as exc:
             raise InvalidParams(exc.message)
-        if start > end:
-            raise InvalidParams('start must be before end')
     elif optional:
         return None, None
 
+    if start > end:
+        raise InvalidParams('start must be before end')
+
+    delta = end - start
+    if delta < MIN_STATS_PERIOD or delta > MAX_STATS_PERIOD:
+        raise InvalidParams(INVALID_PERIOD_ERROR)
+
     return start, end
diff --git a/tests/sentry/api/test_utils.py b/tests/sentry/api/test_utils.py
index b9a33c1294378a..97e13116804082 100644
--- a/tests/sentry/api/test_utils.py
+++ b/tests/sentry/api/test_utils.py
@@ -51,3 +51,21 @@ def test_no_params(self):
         start, end = get_date_range_from_params({}, optional=True)
         assert start is None
         assert end is None
+
+    @freeze_time('2018-12-11 03:21:34')
+    def test_relative_date_range(self):
+        start, end = get_date_range_from_params({
+            'statsPeriodStart': '14d',
+            'statsPeriodEnd': '7d',
+        })
+
+        assert start == datetime.datetime(2018, 11, 27, 3, 21, 34, tzinfo=timezone.utc)
+        assert end == datetime.datetime(2018, 12, 4, 3, 21, 34, tzinfo=timezone.utc)
+
+    @freeze_time('2018-12-11 03:21:34')
+    def test_relative_date_range_incomplete(self):
+
+        with self.assertRaises(InvalidParams):
+            start, end = get_date_range_from_params({
+                'statsPeriodStart': '14d',
+            })