diff --git a/src/Network/IPRange.php b/src/Network/IPRange.php
new file mode 100644
--- /dev/null
+++ b/src/Network/IPRange.php
@@ -0,0 +1,67 @@
+<?php
+declare(strict_types=1);
+
+namespace Keruald\OmniTools\Network;
+
+use Countable;
+use InvalidArgumentException;
+
+abstract class IPRange implements Countable {
+
+    ///
+    /// Constructors
+    ///
+
+    public static function from (string $format) : self {
+        $data = explode("/", $format, 2);
+
+        if (IP::isIPv4($data[0])) {
+            return new IPv4Range($data[0], (int)$data[1]);
+        }
+
+        if (IP::isIPv6($data[0])) {
+            return new IPv6Range($data[0], (int)$data[1]);
+        }
+
+        throw new InvalidArgumentException();
+    }
+
+    ///
+    /// Getters and setters
+    ///
+
+    public abstract function getBase () : string;
+    public abstract function setBase (string $base) : void;
+
+    public abstract function getNetworkBits () : int;
+    public abstract function setNetworkBits (int $networkBits) : void;
+
+    ///
+    /// Helper methods
+    ///
+
+    public abstract function contains (string $ip) : bool;
+    public abstract function getFirst () : string;
+    public abstract function getLast () : string;
+
+    ///
+    /// Countable methods
+    ///
+
+    public abstract function count () : int;
+
+    ///
+    /// Data sources
+    ///
+
+    /**
+     * @return IPRange[]
+     */
+    public static function getLoopbackRanges () : array {
+        return [
+            "IPv4" => self::from("127.0.0.0/8"),
+            "IPv6" => self::from("::1/128"),
+        ];
+    }
+
+}
diff --git a/src/Network/IPv4Range.php b/src/Network/IPv4Range.php
new file mode 100644
--- /dev/null
+++ b/src/Network/IPv4Range.php
@@ -0,0 +1,107 @@
+<?php
+
+namespace Keruald\OmniTools\Network;
+
+use Countable;
+use InvalidArgumentException;
+
+class IPv4Range extends IPRange {
+
+    /**
+     * @var string
+     */
+    private $base;
+
+    /**
+     * @var int
+     */
+    private $networkBits;
+
+    ///
+    /// Constructors
+    ///
+
+    public function __construct (string $base, int $networkBits) {
+        $this->setBase($base);
+        $this->setNetworkBits($networkBits);
+    }
+
+    ///
+    /// Getters and setters
+    ///
+
+    /**
+     * @return string
+     */
+    public function getBase () : string {
+        return $this->base;
+    }
+
+    /**
+     * @param string $base
+     */
+    public function setBase (string $base) : void {
+        if (!IP::isIPv4($base)) {
+            throw new InvalidArgumentException;
+        }
+
+        $this->base = $base;
+    }
+
+    /**
+     * @return int
+     */
+    public function getNetworkBits () : int {
+        return $this->networkBits;
+    }
+
+    /**
+     * @param int $networkBits
+     */
+    public function setNetworkBits (int $networkBits) : void {
+        if ($networkBits < 0 || $networkBits > 32) {
+            throw new InvalidArgumentException;
+        }
+
+        $this->networkBits = $networkBits;
+    }
+
+    ///
+    /// Helper methods
+    ///
+
+    public function getFirst () : string {
+        return $this->base;
+    }
+
+    public function getLast () : string {
+        return long2ip(ip2long($this->base) + 2 ** $this->count() - 1);
+    }
+
+    public function contains (string $ip) : bool {
+        if (!IP::isIP($ip)) {
+            throw new InvalidArgumentException;
+        }
+
+        if (!IP::isIPv4($ip)) {
+            return false;
+        }
+
+        $ipAsLong = ip2long($ip);
+        $baseAsLong = ip2long($this->base);
+
+        return $ipAsLong >= $baseAsLong
+            && $ipAsLong <= $baseAsLong + $this->count() - 1;
+
+        return false;
+    }
+
+    ///
+    /// Countable interface
+    ///
+
+    public function count () : int {
+        return 32 - $this->networkBits;
+    }
+
+}
diff --git a/src/Network/IPv6.php b/src/Network/IPv6.php
new file mode 100644
--- /dev/null
+++ b/src/Network/IPv6.php
@@ -0,0 +1,98 @@
+<?php
+
+namespace Keruald\OmniTools\Network;
+
+use InvalidArgumentException;
+
+class IPv6 extends IP {
+
+    /**
+     * @var string
+     */
+    private $ip;
+
+    ///
+    /// Constructors
+    ///
+
+    public function __construct (string $ip) {
+        $this->ip = $ip;
+    }
+
+    public static function from (string $ip) : self {
+        $ipv6 = new self($ip);
+
+        if (!$ipv6->isValid()) {
+            throw new InvalidArgumentException;
+        }
+
+        $ipv6->normalize();
+
+        return $ipv6;
+    }
+
+    public static function fromBinaryBits (array $bits) : self {
+        $fullBits = $bits + array_fill(0, 128, 0);
+        $hextets = [];
+
+        for ($i = 0 ; $i < 8 ; $i++) {
+            // Read 16 bits
+            $slice = implode("", array_slice($fullBits, $i * 16, 16));
+            $hextets[] = base_convert($slice, 2, 16);
+        }
+
+        return self::from(implode(":", $hextets));
+    }
+
+    ///
+    /// Helper methods
+    ///
+
+    public function isValid () : bool {
+        return IP::isIPv6($this->ip);
+    }
+
+    public function increment (int $increment = 1) : self {
+        if ($increment === 0) {
+            return $this;
+        }
+
+        if ($increment < 0) {
+            throw new InvalidArgumentException("This method doesn't support decrementation.");
+        }
+
+        $ipAsNumericBinary = inet_pton($this->ip);
+
+        // See https://gist.github.com/little-apps/88bbd23576008a84e0b6
+        $i = strlen($ipAsNumericBinary) - 1;
+        $remainder = $increment;
+
+        while ($remainder > 0 && $i >= 0) {
+            $sum = ord($ipAsNumericBinary[$i]) + $remainder;
+            $remainder = $sum / 256;
+            $ipAsNumericBinary[$i] = chr($sum % 256);
+
+            --$i;
+        }
+
+        $this->ip = inet_ntop($ipAsNumericBinary);
+        return $this;
+    }
+
+    public function normalize () : self {
+        $this->ip = inet_ntop(inet_pton($this->ip));
+        return $this;
+    }
+
+    public function isNormalized() : bool {
+        return $this->ip === inet_ntop(inet_pton($this->ip));
+    }
+
+    ///
+    /// Magic methods
+    ///
+
+    public function __toString () : string {
+        return $this->ip;
+    }
+}
diff --git a/src/Network/IPv6Range.php b/src/Network/IPv6Range.php
new file mode 100644
--- /dev/null
+++ b/src/Network/IPv6Range.php
@@ -0,0 +1,119 @@
+<?php
+
+namespace Keruald\OmniTools\Network;
+
+use Countable;
+use InvalidArgumentException;
+
+class IPv6Range extends IPRange {
+
+    /**
+     * @var string
+     */
+    private $base;
+
+    /**
+     * @var int
+     */
+    private $networkBits;
+
+    ///
+    /// Constructors
+    ///
+
+    public function __construct (string $base, int $networkBits) {
+        $this->setBase($base);
+        $this->setNetworkBits($networkBits);
+    }
+
+    ///
+    /// Getters and setters
+    ///
+
+    /**
+     * @return string
+     */
+    public function getBase () : string {
+        return $this->base;
+    }
+
+    /**
+     * @param string $base
+     */
+    public function setBase (string $base) : void {
+        if (!IP::isIPv6($base)) {
+            throw new InvalidArgumentException;
+        }
+
+        $this->base = $base;
+    }
+
+    /**
+     * @return int
+     */
+    public function getNetworkBits () : int {
+        return $this->networkBits;
+    }
+
+    /**
+     * @param int $networkBits
+     */
+    public function setNetworkBits (int $networkBits) : void {
+        if ($networkBits < 0 || $networkBits > 128) {
+            throw new InvalidArgumentException;
+        }
+
+        $this->networkBits = $networkBits;
+    }
+
+    ///
+    /// Helper methods
+    ///
+
+    public function getFirst () : string {
+        return $this->base;
+    }
+
+    public function getLast () : string {
+        if ($this->count() === 0) {
+            return $this->base;
+        }
+
+        $base = inet_pton($this->getFirst());
+        $mask = inet_pton($this->getInversedMask());
+        return inet_ntop($base | $mask);
+    }
+
+    private function getInversedMask () : string {
+        $bits = array_fill(0, $this->networkBits, 0) + array_fill(0, 128, 1);
+
+        return (string)IPv6::fromBinaryBits($bits);
+    }
+
+    public function contains (string $ip) : bool {
+        if (!IP::isIP($ip)) {
+            throw new InvalidArgumentException;
+        }
+
+        if (IP::isIPv4($ip)) {
+            $ip = "::ffff:" . $ip; // IPv4-mapped IPv6 address
+        }
+
+        $baseAsNumericBinary = inet_pton($this->getFirst());
+        $lastAsNumericBinary = inet_pton($this->getLast());
+        $ipAsNumericBinary   = inet_pton($ip);
+
+        return strlen($ipAsNumericBinary) == strlen($baseAsNumericBinary)
+            && $ipAsNumericBinary >= $baseAsNumericBinary
+            && $ipAsNumericBinary <= $lastAsNumericBinary;
+    }
+
+    ///
+    /// Countable interface
+    ///
+
+    public function count () : int {
+        return 128 - $this->networkBits;
+    }
+
+}
diff --git a/tests/Network/IPv4RangeTest.php b/tests/Network/IPv4RangeTest.php
new file mode 100644
--- /dev/null
+++ b/tests/Network/IPv4RangeTest.php
@@ -0,0 +1,47 @@
+<?php
+
+namespace Keruald\OmniTools\Tests\Network;
+
+use Keruald\OmniTools\Network\IPRange;
+use PHPUnit\Framework\TestCase;
+
+class IPv4RangeTest extends TestCase {
+
+    /**
+     * @var IPRange
+     */
+    protected $range;
+
+    ///
+    /// Fixtures
+    ///
+
+    protected function setUp () : void {
+        $this->range = IPRange::from("216.66.0.0/18");
+    }
+
+    ///
+    /// Tests
+    ///
+
+    public function testGetBase () : void {
+        $this->assertEquals("216.66.0.0", $this->range->getBase());
+    }
+
+    public function testGetNetworkBits () : void {
+        $this->assertEquals(18, $this->range->getNetworkBits());
+    }
+
+    public function testCount () : void {
+        $this->assertEquals(14, $this->range->count()); // 14 + 18 = 32 bits
+    }
+
+    public function testGetFirst () : void {
+        $this->assertEquals("216.66.0.0", $this->range->getFirst());
+    }
+
+    public function testGetLast () : void {
+        $this->assertEquals("216.66.63.255", $this->range->getLast());
+    }
+
+}
diff --git a/tests/Network/IPv6RangeTest.php b/tests/Network/IPv6RangeTest.php
new file mode 100644
--- /dev/null
+++ b/tests/Network/IPv6RangeTest.php
@@ -0,0 +1,55 @@
+<?php
+
+namespace Keruald\OmniTools\Tests\Network;
+
+use Keruald\OmniTools\Network\IPRange;
+use PHPUnit\Framework\TestCase;
+
+class IPv6RangeTest extends TestCase {
+
+    /**
+     * @var IPRange
+     */
+    protected $range;
+
+    ///
+    /// Fixtures
+    ///
+
+    protected function setUp () : void {
+        $this->range = IPRange::from("2001:400::/23");
+    }
+
+    ///
+    /// Tests
+    ///
+
+    public function testGetBase () : void {
+        $this->assertEquals("2001:400::", $this->range->getBase());
+    }
+
+    public function testGetNetworkBits () : void {
+        $this->assertEquals(23, $this->range->getNetworkBits());
+    }
+
+    public function testCount () : void {
+        $this->assertEquals(105, $this->range->count()); // 23 + 105 = 128 bits
+    }
+
+    public function testGetFirst () : void {
+        $this->assertEquals("2001:400::", $this->range->getFirst());
+    }
+
+    public function testGetLast () : void {
+        $this->assertEquals("2001:5ff:ffff:ffff:ffff:ffff:ffff:ffff", $this->range->getLast());
+    }
+
+    public function testContains () : void {
+        $this->assertTrue($this->range->contains("2001:431::af"));
+    }
+
+    public function testContainsWorksWithIPv4MappedIPv6Address () : void {
+        $this->assertTrue(IPRange::from("::ffff:0.0.0.0/96")->contains("1.2.3.4"));
+    }
+
+}