diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2b33aae7..d9d5d9fa 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -12,10 +12,12 @@ For a full diff see [`dcd4cfb...main`][dcd4cfb...main].
 
 * Added `Json` ([#2]), by [@localheinz]
 * Added `Schema` ([#3]), by [@localheinz]
+* Added `Decoder` ([#5]), by [@localheinz]
 
 [dcd4cfb...main]: https://github.com/ergebnis/json-schema-validator/compare/dcd4cfb...main
 
 [#2]: https://github.com/ergebnis/json-schema-validator/pull/2
 [#3]: https://github.com/ergebnis/json-schema-validator/pull/3
+[#5]: https://github.com/ergebnis/json-schema-validator/pull/5
 
 [@localheinz]: https://github.com/localheinz
diff --git a/infection.json b/infection.json
index a50b766f..627741b8 100644
--- a/infection.json
+++ b/infection.json
@@ -3,8 +3,8 @@
   "logs": {
     "text": ".build/infection/infection-log.txt"
   },
-  "minCoveredMsi": 92,
-  "minMsi": 88,
+  "minCoveredMsi": 82,
+  "minMsi": 78,
   "phpUnit": {
     "configDir": "test\/Unit"
   },
diff --git a/psalm-baseline.xml b/psalm-baseline.xml
index 76c390b0..e4b5c627 100644
--- a/psalm-baseline.xml
+++ b/psalm-baseline.xml
@@ -1,11 +1,37 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <files psalm-version="4.4.1@9fd7a7d885b3a216cff8dec9d8c21a132f275224">
+  <file src="src/Decoder.php">
+    <MixedAssignment occurrences="2">
+      <code>$decoded</code>
+      <code>$decoded</code>
+    </MixedAssignment>
+    <MixedInferredReturnType occurrences="2">
+      <code>null|array|bool|float|int|\stdClass|string</code>
+      <code>null|array|bool|float|int|string</code>
+    </MixedInferredReturnType>
+    <MixedReturnStatement occurrences="2">
+      <code>$decoded</code>
+      <code>$decoded</code>
+    </MixedReturnStatement>
+  </file>
   <file src="src/Json.php">
     <MixedAssignment occurrences="2">
       <code>$decoded</code>
       <code>$decoded</code>
     </MixedAssignment>
   </file>
+  <file src="test/DataProvider/JsonProvider.php">
+    <MoreSpecificReturnType occurrences="2">
+      <code>\Generator&lt;string, array{0: string}&gt;</code>
+      <code>\Generator&lt;string, array{0: string}&gt;</code>
+    </MoreSpecificReturnType>
+  </file>
+  <file src="test/Unit/DecoderTest.php">
+    <MixedAssignment occurrences="2">
+      <code>$expected</code>
+      <code>$expected</code>
+    </MixedAssignment>
+  </file>
   <file src="test/Unit/SchemaTest.php">
     <MixedAssignment occurrences="1">
       <code>$decoded</code>
diff --git a/src/Decoder.php b/src/Decoder.php
new file mode 100644
index 00000000..a6e831e1
--- /dev/null
+++ b/src/Decoder.php
@@ -0,0 +1,55 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * Copyright (c) 2021 Andreas Möller
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE.md file that was distributed with this source code.
+ *
+ * @see https://github.com/ergebnis/json-schema-validator
+ */
+
+namespace Ergebnis\Json\SchemaValidator;
+
+final class Decoder
+{
+    /**
+     * @throws Exception\InvalidJson
+     *
+     * @return null|array|bool|float|int|string
+     */
+    public function decodeAssociative(string $value)
+    {
+        $decoded = \json_decode(
+            $value,
+            true
+        );
+
+        if (null === $decoded && \JSON_ERROR_NONE !== \json_last_error()) {
+            throw Exception\InvalidJson::string();
+        }
+
+        return $decoded;
+    }
+
+    /**
+     * @throws Exception\InvalidJson
+     *
+     * @return null|array|bool|float|int|\stdClass|string
+     */
+    public function decodeNonAssociative(string $value)
+    {
+        $decoded = \json_decode(
+            $value,
+            false
+        );
+
+        if (null === $decoded && \JSON_ERROR_NONE !== \json_last_error()) {
+            throw Exception\InvalidJson::string();
+        }
+
+        return $decoded;
+    }
+}
diff --git a/test/DataProvider/JsonProvider.php b/test/DataProvider/JsonProvider.php
new file mode 100644
index 00000000..f8813273
--- /dev/null
+++ b/test/DataProvider/JsonProvider.php
@@ -0,0 +1,66 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * Copyright (c) 2021 Andreas Möller
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE.md file that was distributed with this source code.
+ *
+ * @see https://github.com/ergebnis/json-schema-validator
+ */
+
+namespace Ergebnis\Json\SchemaValidator\Test\DataProvider;
+
+use Ergebnis\Test\Util;
+
+final class JsonProvider
+{
+    use Util\Helper;
+
+    /**
+     * @return \Generator<string, array{0: string}>
+     */
+    public static function validString(): \Generator
+    {
+        yield from self::provideDataForValues(\array_map(static function (string $file): string {
+            $contents
+                = \file_get_contents($file);
+
+            if (!\is_string($contents)) {
+                throw new \RuntimeException(\sprintf(
+                    'File "%s" does not exist or can not be read.',
+                    $file
+                ));
+            }
+
+            return $contents;
+        }, self::filesContainingValidJson()));
+    }
+
+    /**
+     * @return \Generator<string, array{0: string}>
+     */
+    public function validFile(): \Generator
+    {
+        yield from self::provideDataForValues(self::filesContainingValidJson());
+    }
+
+    /**
+     * @return array<string, string>
+     */
+    private static function filesContainingValidJson(): array
+    {
+        return [
+            'array' => __DIR__ . '/../Fixture/Json/valid/array.json',
+            'bool-false' => __DIR__ . '/../Fixture/Json/valid/bool-false.json',
+            'bool-true' => __DIR__ . '/../Fixture/Json/valid/bool-true.json',
+            'float' => __DIR__ . '/../Fixture/Json/valid/float.json',
+            'int' => __DIR__ . '/../Fixture/Json/valid/int.json',
+            'object' => __DIR__ . '/../Fixture/Json/valid/object.json',
+            'string-arbitrary' => __DIR__ . '/../Fixture/Json/valid/string-arbitrary.json',
+            'string-empty' => __DIR__ . '/../Fixture/Json/valid/string-empty.json',
+        ];
+    }
+}
diff --git a/test/Unit/DecoderTest.php b/test/Unit/DecoderTest.php
new file mode 100644
index 00000000..9007eb3c
--- /dev/null
+++ b/test/Unit/DecoderTest.php
@@ -0,0 +1,93 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * Copyright (c) 2021 Andreas Möller
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE.md file that was distributed with this source code.
+ *
+ * @see https://github.com/ergebnis/json-schema-validator
+ */
+
+namespace Ergebnis\Json\SchemaValidator\Test\Unit;
+
+use Ergebnis\Json\SchemaValidator\Decoder;
+use Ergebnis\Json\SchemaValidator\Exception;
+use Ergebnis\Test\Util;
+use PHPUnit\Framework;
+
+/**
+ * @internal
+ *
+ * @covers \Ergebnis\Json\SchemaValidator\Decoder
+ *
+ * @uses \Ergebnis\Json\SchemaValidator\Exception\InvalidJson
+ */
+final class DecoderTest extends Framework\TestCase
+{
+    use Util\Helper;
+
+    public function testDecodeAssociativeThrowsExceptionWhenValueCanNotBeDecoded(): void
+    {
+        $value = <<<'TXT'
+{
+    "foo:
+TXT;
+
+        $decoder = new Decoder();
+
+        $this->expectException(Exception\InvalidJson::class);
+
+        $decoder->decodeAssociative($value);
+    }
+
+    /**
+     * @dataProvider \Ergebnis\Json\SchemaValidator\Test\DataProvider\JsonProvider::validString()
+     */
+    public function testDecodeAssociativeReturnsJsonDecodedValue(string $encoded): void
+    {
+        $decoder = new Decoder();
+
+        $decoded = $decoder->decodeAssociative($encoded);
+
+        $expected = \json_decode(
+            $encoded,
+            true
+        );
+
+        self::assertSame($expected, $decoded);
+    }
+
+    public function testDecodeNonAssociativeThrowsExceptionWhenValueCanNotBeDecoded(): void
+    {
+        $value = <<<'TXT'
+{
+    "foo:
+TXT;
+
+        $decoder = new Decoder();
+
+        $this->expectException(Exception\InvalidJson::class);
+
+        $decoder->decodeAssociative($value);
+    }
+
+    /**
+     * @dataProvider \Ergebnis\Json\SchemaValidator\Test\DataProvider\JsonProvider::validString()
+     */
+    public function testDecodeNonAssociativeReturnsJsonDecodedValue(string $encoded): void
+    {
+        $decoder = new Decoder();
+
+        $decoded = $decoder->decodeNonAssociative($encoded);
+
+        $expected = \json_decode(
+            $encoded,
+            false
+        );
+
+        self::assertEquals($expected, $decoded);
+    }
+}
diff --git a/test/Unit/JsonTest.php b/test/Unit/JsonTest.php
index 43ae2e35..202275af 100644
--- a/test/Unit/JsonTest.php
+++ b/test/Unit/JsonTest.php
@@ -43,7 +43,7 @@ public function testFromStringThrowsWhenValueIsNotJson(): void
     }
 
     /**
-     * @dataProvider provideValidJsonString
+     * @dataProvider \Ergebnis\Json\SchemaValidator\Test\DataProvider\JsonProvider::validString()
      */
     public function testFromStringReturnsJsonWhenValueIsValidJson(string $encoded): void
     {
@@ -52,27 +52,6 @@ public function testFromStringReturnsJsonWhenValueIsValidJson(string $encoded):
         self::assertSame($encoded, $json->encoded());
     }
 
-    /**
-     * @return \Generator<string, array{0: string}>
-     */
-    public function provideValidJsonString(): \Generator
-    {
-        foreach (self::filesContainingValidJson() as $key => $value) {
-            $content = \file_get_contents($value);
-
-            if (!\is_string($content)) {
-                throw new \RuntimeException(\sprintf(
-                    'File "%s" does not exist or can not be read.',
-                    $value
-                ));
-            }
-
-            yield $key => [
-                $content,
-            ];
-        }
-    }
-
     public function testFromFileThrowsWhenFileDoesNotExist(): void
     {
         $file = __DIR__ . '/../Fixture/Json/does-not-exist.json';
@@ -101,7 +80,7 @@ public function testFromFileThrowsWhenFileDoesNotContainValidJson(): void
     }
 
     /**
-     * @dataProvider provideValidJsonFile
+     * @dataProvider \Ergebnis\Json\SchemaValidator\Test\DataProvider\JsonProvider::validFile()
      */
     public function testFromFileReturnsJsonWhenFileContainsValidJson(string $file): void
     {
@@ -109,33 +88,4 @@ public function testFromFileReturnsJsonWhenFileContainsValidJson(string $file):
 
         self::assertStringEqualsFile($file, $json->encoded());
     }
-
-    /**
-     * @return \Generator<string, array{0: string}>
-     */
-    public function provideValidJsonFile(): \Generator
-    {
-        foreach (self::filesContainingValidJson() as $key => $value) {
-            yield $key => [
-                $value,
-            ];
-        }
-    }
-
-    /**
-     * @return array<string, string>
-     */
-    private static function filesContainingValidJson(): array
-    {
-        return [
-            'array' => __DIR__ . '/../Fixture/Json/valid/array.json',
-            'bool-false' => __DIR__ . '/../Fixture/Json/valid/bool-false.json',
-            'bool-true' => __DIR__ . '/../Fixture/Json/valid/bool-true.json',
-            'float' => __DIR__ . '/../Fixture/Json/valid/float.json',
-            'int' => __DIR__ . '/../Fixture/Json/valid/int.json',
-            'object' => __DIR__ . '/../Fixture/Json/valid/object.json',
-            'string-arbitrary' => __DIR__ . '/../Fixture/Json/valid/string-arbitrary.json',
-            'string-empty' => __DIR__ . '/../Fixture/Json/valid/string-empty.json',
-        ];
-    }
 }