diff --git a/src/Invoice/Calculator/DateInvoiceCalculator.php b/src/Invoice/Calculator/DateInvoiceCalculator.php
new file mode 100644
index 00000000..9ba020af
--- /dev/null
+++ b/src/Invoice/Calculator/DateInvoiceCalculator.php
@@ -0,0 +1,32 @@
+<?php
+
+/*
+ * This file is part of the Kimai time-tracking app.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace App\Invoice\Calculator;
+
+use App\Entity\Timesheet;
+use App\Invoice\CalculatorInterface;
+
+/**
+ * A calculator that sums up the timesheet records for each day.
+ */
+class DateInvoiceCalculator extends AbstractSumInvoiceCalculator implements CalculatorInterface
+{
+    protected function calculateSumIdentifier(Timesheet $timesheet): string
+    {
+        return $timesheet->getBegin()->format('Y-m-d');
+    }
+
+    /**
+     * @return string
+     */
+    public function getId(): string
+    {
+        return 'date';
+    }
+}
diff --git a/tests/Invoice/Calculator/DateInvoiceCalculatorTest.php b/tests/Invoice/Calculator/DateInvoiceCalculatorTest.php
new file mode 100644
index 00000000..51637bae
--- /dev/null
+++ b/tests/Invoice/Calculator/DateInvoiceCalculatorTest.php
@@ -0,0 +1,148 @@
+<?php
+
+/*
+ * This file is part of the Kimai time-tracking app.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace App\Tests\Invoice\Calculator;
+
+use App\Entity\Activity;
+use App\Entity\Customer;
+use App\Entity\InvoiceTemplate;
+use App\Entity\Project;
+use App\Entity\Timesheet;
+use App\Entity\User;
+use App\Invoice\Calculator\DateInvoiceCalculator;
+use App\Model\InvoiceModel;
+use App\Repository\Query\InvoiceQuery;
+use DateTime;
+
+/**
+ * @covers \App\Invoice\Calculator\DateInvoiceCalculator
+ * @covers \App\Invoice\Calculator\AbstractSumInvoiceCalculator
+ * @covers \App\Invoice\Calculator\AbstractMergedCalculator
+ * @covers \App\Invoice\Calculator\AbstractCalculator
+ */
+class DateInvoiceCalculatorTest extends AbstractCalculatorTest
+{
+    public function testEmptyModel()
+    {
+        $this->assertEmptyModel(new DateInvoiceCalculator());
+    }
+
+    public function testWithMultipleEntries()
+    {
+        $customer = new Customer();
+        $template = new InvoiceTemplate();
+        $template->setVat(19);
+
+        $user = $this->getMockBuilder(User::class)->setMethods(['getId'])->disableOriginalConstructor()->getMock();
+        $user->method('getId')->willReturn(1);
+
+        $project1 = $this->getMockBuilder(Project::class)->setMethods(['getId'])->disableOriginalConstructor()->getMock();
+        $project1->method('getId')->willReturn(1);
+
+        $project2 = $this->getMockBuilder(Project::class)->setMethods(['getId'])->disableOriginalConstructor()->getMock();
+        $project2->method('getId')->willReturn(2);
+
+        $project3 = $this->getMockBuilder(Project::class)->setMethods(['getId'])->disableOriginalConstructor()->getMock();
+        $project3->method('getId')->willReturn(3);
+
+        $timesheet = new Timesheet();
+        $timesheet
+            ->setBegin(new DateTime('2018-11-29'))
+            ->setEnd(new DateTime())
+            ->setDuration(3600)
+            ->setRate(293.27)
+            ->setUser($user)
+            ->setActivity((new Activity())->setName('sdsd'))
+            ->setProject($project1);
+
+        $timesheet2 = new Timesheet();
+        $timesheet2
+            ->setBegin(new DateTime('2018-11-29'))
+            ->setEnd(new DateTime())
+            ->setDuration(400)
+            ->setRate(84.75)
+            ->setUser($user)
+            ->setActivity((new Activity())->setName('bar'))
+            ->setProject($project2);
+
+        $timesheet3 = new Timesheet();
+        $timesheet3
+            ->setBegin(new DateTime('2018-11-28'))
+            ->setEnd(new DateTime())
+            ->setDuration(1800)
+            ->setRate(111.11)
+            ->setUser($user)
+            ->setActivity((new Activity())->setName('foo'))
+            ->setProject($project1);
+
+        $timesheet4 = new Timesheet();
+        $timesheet4
+            ->setBegin(new DateTime())
+            ->setEnd(new DateTime('2018-11-28'))
+            ->setDuration(400)
+            ->setRate(1947.99)
+            ->setUser($user)
+            ->setActivity((new Activity())->setName('blub'))
+            ->setProject($project2);
+
+        $timesheet5 = new Timesheet();
+        $timesheet5
+            ->setBegin(new DateTime('2018-11-28'))
+            ->setEnd(new DateTime())
+            ->setDuration(400)
+            ->setRate(84)
+            ->setUser(new User())
+            ->setActivity(new Activity())
+            ->setProject($project3);
+
+        $entries = [$timesheet, $timesheet2, $timesheet3, $timesheet4, $timesheet5];
+
+        $query = new InvoiceQuery();
+        $query->setProject($project1);
+
+        $model = new InvoiceModel();
+        $model->setCustomer($customer);
+        $model->setTemplate($template);
+        $model->setEntries($entries);
+        $model->setQuery($query);
+
+        $sut = new DateInvoiceCalculator();
+        $sut->setModel($model);
+
+        $this->assertEquals('date', $sut->getId());
+        $this->assertEquals(3000.13, $sut->getTotal());
+        $this->assertEquals(19, $sut->getVat());
+        $this->assertEquals('EUR', $sut->getCurrency());
+        $this->assertEquals(2521.12, $sut->getSubtotal());
+        $this->assertEquals(6600, $sut->getTimeWorked());
+        $this->assertEquals(3, count($sut->getEntries()));
+
+        $entries = $sut->getEntries();
+        self::assertCount(3, $entries);
+        $this->assertEquals(378.02, $entries[0]->getRate());
+        $this->assertEquals(195.11, $entries[1]->getRate());
+        $this->assertEquals(1947.99, $entries[2]->getRate());
+        self::assertEquals(2521.12, $entries[0]->getRate() + $entries[1]->getRate() + $entries[2]->getRate());
+    }
+
+    public function testDescriptionByTimesheet()
+    {
+        $this->assertDescription(new DateInvoiceCalculator(), false, false);
+    }
+
+    public function testDescriptionByActivity()
+    {
+        $this->assertDescription(new DateInvoiceCalculator(), false, true);
+    }
+
+    public function testDescriptionByProject()
+    {
+        $this->assertDescription(new DateInvoiceCalculator(), true, false);
+    }
+}
diff --git a/tests/Invoice/Calculator/ProjectInvoiceCalculatorTest.php b/tests/Invoice/Calculator/ProjectInvoiceCalculatorTest.php
index 47c1d130..d9a0de94 100644
--- a/tests/Invoice/Calculator/ProjectInvoiceCalculatorTest.php
+++ b/tests/Invoice/Calculator/ProjectInvoiceCalculatorTest.php
@@ -18,6 +18,7 @@ use App\Entity\User;
 use App\Invoice\Calculator\ProjectInvoiceCalculator;
 use App\Model\InvoiceModel;
 use App\Repository\Query\InvoiceQuery;
+use DateTime;
 
 /**
  * @covers \App\Invoice\Calculator\ProjectInvoiceCalculator
@@ -52,8 +53,8 @@ class ProjectInvoiceCalculatorTest extends AbstractCalculatorTest
 
         $timesheet = new Timesheet();
         $timesheet
-            ->setBegin(new \DateTime())
-            ->setEnd(new \DateTime())
+            ->setBegin(new DateTime())
+            ->setEnd(new DateTime())
             ->setDuration(3600)
             ->setRate(293.27)
             ->setUser($user)
@@ -62,8 +63,8 @@ class ProjectInvoiceCalculatorTest extends AbstractCalculatorTest
 
         $timesheet2 = new Timesheet();
         $timesheet2
-            ->setBegin(new \DateTime())
-            ->setEnd(new \DateTime())
+            ->setBegin(new DateTime())
+            ->setEnd(new DateTime())
             ->setDuration(400)
             ->setRate(84.75)
             ->setUser($user)
@@ -72,8 +73,8 @@ class ProjectInvoiceCalculatorTest extends AbstractCalculatorTest
 
         $timesheet3 = new Timesheet();
         $timesheet3
-            ->setBegin(new \DateTime())
-            ->setEnd(new \DateTime())
+            ->setBegin(new DateTime())
+            ->setEnd(new DateTime())
             ->setDuration(1800)
             ->setRate(111.11)
             ->setUser($user)
@@ -82,8 +83,8 @@ class ProjectInvoiceCalculatorTest extends AbstractCalculatorTest
 
         $timesheet4 = new Timesheet();
         $timesheet4
-            ->setBegin(new \DateTime())
-            ->setEnd(new \DateTime())
+            ->setBegin(new DateTime())
+            ->setEnd(new DateTime())
             ->setDuration(400)
             ->setRate(1947.99)
             ->setUser($user)
@@ -92,8 +93,8 @@ class ProjectInvoiceCalculatorTest extends AbstractCalculatorTest
 
         $timesheet5 = new Timesheet();
         $timesheet5
-            ->setBegin(new \DateTime())
-            ->setEnd(new \DateTime())
+            ->setBegin(new DateTime())
+            ->setEnd(new DateTime())
             ->setDuration(400)
             ->setRate(84)
             ->setUser(new User())
@@ -123,9 +124,11 @@ class ProjectInvoiceCalculatorTest extends AbstractCalculatorTest
         $this->assertEquals(3, count($sut->getEntries()));
 
         $entries = $sut->getEntries();
+        self::assertCount(3, $entries);
         $this->assertEquals(404.38, $entries[0]->getRate());
         $this->assertEquals(2032.74, $entries[1]->getRate());
         $this->assertEquals(84, $entries[2]->getRate());
+        self::assertEquals(2521.12, $entries[0]->getRate() + $entries[1]->getRate() + $entries[2]->getRate());
     }
 
     public function testDescriptionByTimesheet()
diff --git a/translations/invoice-calculator.de.xliff b/translations/invoice-calculator.de.xliff
index ae834fc6..9c8afecc 100644
--- a/translations/invoice-calculator.de.xliff
+++ b/translations/invoice-calculator.de.xliff
@@ -26,6 +26,10 @@
                 <source>project</source>
                 <target>Projekt: ein Eintrag pro Projekt</target>
             </trans-unit>
+            <trans-unit id="date">
+                <source>date</source>
+                <target>Datum: ein Eintrag pro Tag (verwendet Startdatum)</target>
+            </trans-unit>
         </body>
     </file>
 </xliff>
diff --git a/translations/invoice-calculator.en.xliff b/translations/invoice-calculator.en.xliff
index 138dbb71..11305784 100644
--- a/translations/invoice-calculator.en.xliff
+++ b/translations/invoice-calculator.en.xliff
@@ -26,6 +26,10 @@
                 <source>project</source>
                 <target>Project: one entry per project</target>
             </trans-unit>
+            <trans-unit id="date">
+                <source>date</source>
+                <target>Date: one entry per day (uses start date)</target>
+            </trans-unit>
         </body>
     </file>
 </xliff>