diff --git a/RCTAppleHealthKit/RCTAppleHealthKit+Utils.h b/RCTAppleHealthKit/RCTAppleHealthKit+Utils.h
index b2bfcaf7fc1f5951c632335f545595f5f9216f0a..3c44029b63633af9c56e2c58f4945f6014ff366f 100644
--- a/RCTAppleHealthKit/RCTAppleHealthKit+Utils.h
+++ b/RCTAppleHealthKit/RCTAppleHealthKit+Utils.h
@@ -14,10 +14,14 @@
 + (NSString *)buildISO8601StringFromDate:(NSDate *)date;
 + (NSPredicate *)predicateForSamplesToday;
 + (NSPredicate *)predicateForSamplesOnDay:(NSDate *)date;
++ (NSPredicate *)predicateForSamplesBetweenDates:(NSDate *)startDate endDate:(NSDate *)endDate;
 + (NSPredicate *)predicateForSamplesOnDayFromTimestamp:(NSString *)timestamp;
 + (double)doubleValueFromOptions:(NSDictionary *)options;
 + (NSDate *)dateFromOptions:(NSDictionary *)options;
 + (NSDate *)dateFromOptionsDefaultNow:(NSDictionary *)options;
++ (NSDate *)startDateFromOptions:(NSDictionary *)options;
++ (NSDate *)endDateFromOptions:(NSDictionary *)options;
++ (NSDate *)endDateFromOptionsDefaultNow:(NSDictionary *)options;
 + (HKUnit *)hkUnitFromOptions:(NSDictionary *)options;
 
 @end
diff --git a/RCTAppleHealthKit/RCTAppleHealthKit+Utils.m b/RCTAppleHealthKit/RCTAppleHealthKit+Utils.m
index 58bef7c87030914e91a4c446e92ce6c0a22e62fc..8191f960075ffa23fa4db80ad0dc8a1fbe166f8a 100644
--- a/RCTAppleHealthKit/RCTAppleHealthKit+Utils.m
+++ b/RCTAppleHealthKit/RCTAppleHealthKit+Utils.m
@@ -49,6 +49,15 @@
     return [HKQuery predicateForSamplesWithStartDate:startDate endDate:endDate options:HKQueryOptionStrictStartDate];
 }
 
++ (NSPredicate *)predicateForSamplesBetweenDates:(NSDate *)startDate endDate:(NSDate *)endDate {
+    NSCalendar *calendar = [NSCalendar currentCalendar];
+    NSDate *start = [calendar startOfDayForDate:startDate];
+    NSDate *end = endDate;
+//    NSDate *endDate = [calendar dateByAddingUnit:NSCalendarUnitDay value:1 toDate:startDate options:0];
+    return [HKQuery predicateForSamplesWithStartDate:startDate endDate:endDate options:HKQueryOptionStrictStartDate];
+}
+
+
 
 
 + (double)doubleValueFromOptions:(NSDictionary *)options {
@@ -66,7 +75,6 @@
     return date;
 }
 
-
 + (NSDate *)dateFromOptionsDefaultNow:(NSDictionary *)options {
     NSString *dateString = [options objectForKey:@"date"];
     if(dateString != nil){
@@ -81,6 +89,44 @@
     return now;
 }
 
+
+//TODO: make a generic function that can return NSDate by key... have 'default now' as option
+
+
++ (NSDate *)startDateFromOptions:(NSDictionary *)options {
+    NSString *dateString = [options objectForKey:@"startDate"];
+    NSDate *date;
+    if(dateString != nil){
+        date = [RCTAppleHealthKit parseISO8601DateFromString:dateString];
+        return date;
+    }
+    return date;
+}
+
++ (NSDate *)endDateFromOptions:(NSDictionary *)options {
+    NSString *dateString = [options objectForKey:@"endDate"];
+    NSDate *date;
+    if(dateString != nil){
+        date = [RCTAppleHealthKit parseISO8601DateFromString:dateString];
+    }
+    return date;
+}
+
++ (NSDate *)endDateFromOptionsDefaultNow:(NSDictionary *)options {
+    NSString *dateString = [options objectForKey:@"endDate"];
+    NSDate *date;
+    if(dateString != nil){
+        date = [RCTAppleHealthKit parseISO8601DateFromString:dateString];
+        return date;
+    }
+    if(date == nil){
+        date = [NSDate date];
+    }
+    return date;
+}
+
+
+
 + (HKUnit *)hkUnitFromOptions:(NSDictionary *)options {
     NSString *unitString = [options objectForKey:@"unit"];
     HKUnit *theUnit;