diff --git a/okcurl/src/main/java/okhttp3/curl/Main.kt b/okcurl/src/main/java/okhttp3/curl/Main.kt
index 943391176..600d37344 100644
--- a/okcurl/src/main/java/okhttp3/curl/Main.kt
+++ b/okcurl/src/main/java/okhttp3/curl/Main.kt
@@ -21,6 +21,7 @@ import com.github.rvesse.airline.annotations.Arguments
 import com.github.rvesse.airline.annotations.Command
 import com.github.rvesse.airline.annotations.Option
 import okhttp3.MediaType
+import okhttp3.MediaType.Companion.toMediaTypeOrNull
 import okhttp3.OkHttpClient
 import okhttp3.Protocol
 import okhttp3.Request
@@ -214,7 +215,7 @@ class Main : Runnable {
       return@let null
     } ?: "application/x-www-form-urlencoded"
 
-    return MediaType.parse(mimeType)
+    return mimeType.toMediaTypeOrNull()
   }
 
   private fun close() {
diff --git a/okhttp-dnsoverhttps/src/main/java/okhttp3/dnsoverhttps/DnsOverHttps.kt b/okhttp-dnsoverhttps/src/main/java/okhttp3/dnsoverhttps/DnsOverHttps.kt
index 8720321d3..7d38825bc 100644
--- a/okhttp-dnsoverhttps/src/main/java/okhttp3/dnsoverhttps/DnsOverHttps.kt
+++ b/okhttp-dnsoverhttps/src/main/java/okhttp3/dnsoverhttps/DnsOverHttps.kt
@@ -21,6 +21,7 @@ import okhttp3.Callback
 import okhttp3.Dns
 import okhttp3.HttpUrl
 import okhttp3.MediaType
+import okhttp3.MediaType.Companion.toMediaType
 import okhttp3.OkHttpClient
 import okhttp3.Protocol
 import okhttp3.Request
@@ -302,7 +303,7 @@ class DnsOverHttps internal constructor(builder: Builder) : Dns {
   }
 
   companion object {
-    val DNS_MESSAGE: MediaType = MediaType.get("application/dns-message")
+    val DNS_MESSAGE: MediaType = "application/dns-message".toMediaType()
     const val MAX_RESPONSE_SIZE = 64 * 1024
 
     private fun buildBootstrapClient(builder: Builder): Dns {
diff --git a/okhttp-sse/src/main/java/okhttp3/internal/sse/ServerSentEventReader.kt b/okhttp-sse/src/main/java/okhttp3/internal/sse/ServerSentEventReader.kt
index 98e4d0f97..ca2ee2e1e 100644
--- a/okhttp-sse/src/main/java/okhttp3/internal/sse/ServerSentEventReader.kt
+++ b/okhttp-sse/src/main/java/okhttp3/internal/sse/ServerSentEventReader.kt
@@ -15,6 +15,7 @@
  */
 package okhttp3.internal.sse
 
+import okhttp3.internal.toLongOrDefault
 import okio.Buffer
 import okio.BufferedSource
 import okio.ByteString.Companion.encodeUtf8
@@ -151,11 +152,7 @@ class ServerSentEventReader(
     @Throws(IOException::class)
     private fun BufferedSource.readRetryMs(): Long {
       val retryString = readUtf8LineStrict()
-      return try {
-        retryString.toLong()
-      } catch (_: NumberFormatException) {
-        -1L
-      }
+      return retryString.toLongOrDefault(-1L)
     }
   }
 }
diff --git a/okhttp/src/main/java/okhttp3/Cache.kt b/okhttp/src/main/java/okhttp3/Cache.kt
index ea8d81f05..efa7ba675 100644
--- a/okhttp/src/main/java/okhttp3/Cache.kt
+++ b/okhttp/src/main/java/okhttp3/Cache.kt
@@ -15,6 +15,7 @@
  */
 package okhttp3
 
+import okhttp3.MediaType.Companion.toMediaTypeOrNull
 import okhttp3.internal.EMPTY_HEADERS
 import okhttp3.internal.cache.CacheRequest
 import okhttp3.internal.cache.CacheStrategy
@@ -24,6 +25,7 @@ import okhttp3.internal.http.HttpMethod
 import okhttp3.internal.http.StatusLine
 import okhttp3.internal.io.FileSystem
 import okhttp3.internal.platform.Platform
+import okhttp3.internal.toLongOrDefault
 import okio.Buffer
 import okio.BufferedSink
 import okio.BufferedSource
@@ -676,17 +678,9 @@ class Cache internal constructor(
       }.buffer()
     }
 
-    override fun contentType(): MediaType? {
-      return if (contentType != null) MediaType.parse(contentType) else null
-    }
+    override fun contentType(): MediaType? = contentType?.toMediaTypeOrNull()
 
-    override fun contentLength(): Long {
-      return try {
-        contentLength?.toLong() ?: -1
-      } catch (_: NumberFormatException) {
-        -1L
-      }
-    }
+    override fun contentLength(): Long = contentLength?.toLongOrDefault(-1L) ?: -1L
 
     override fun source(): BufferedSource = bodySource
   }
diff --git a/okhttp/src/main/java/okhttp3/Cookie.kt b/okhttp/src/main/java/okhttp3/Cookie.kt
index fd2078ff4..41e9d9c7f 100644
--- a/okhttp/src/main/java/okhttp3/Cookie.kt
+++ b/okhttp/src/main/java/okhttp3/Cookie.kt
@@ -16,13 +16,13 @@
 package okhttp3
 
 import okhttp3.internal.UTC
-import okhttp3.internal.delimiterOffset
-import okhttp3.internal.indexOfControlOrNonAscii
-import okhttp3.internal.trimSubstring
-import okhttp3.internal.http.HttpDate
 import okhttp3.internal.canParseAsIpAddress
+import okhttp3.internal.delimiterOffset
+import okhttp3.internal.http.HttpDate
+import okhttp3.internal.indexOfControlOrNonAscii
 import okhttp3.internal.publicsuffix.PublicSuffixDatabase
 import okhttp3.internal.toCanonicalHost
+import okhttp3.internal.trimSubstring
 import java.util.Calendar
 import java.util.Collections
 import java.util.Date
@@ -532,11 +532,10 @@ data class Cookie private constructor(
     }
 
     /**
-     * Returns the positive value if `attributeValue` is positive, or [Long.MIN_VALUE] if it is
-     * either 0 or negative. If the value is positive but out of range, this returns
-     * [Long.MAX_VALUE].
+     * Returns the positive value if [s] is positive, or [Long.MIN_VALUE] if it is either 0 or
+     * negative. If the value is positive but out of range, this returns [Long.MAX_VALUE].
      *
-     * @throws NumberFormatException if `s` is not an integer of any precision.
+     * @throws NumberFormatException if [s] is not an integer of any precision.
      */
     private fun parseMaxAge(s: String): Long {
       try {
diff --git a/okhttp/src/main/java/okhttp3/FormBody.kt b/okhttp/src/main/java/okhttp3/FormBody.kt
index f12af9bdc..235840ad4 100644
--- a/okhttp/src/main/java/okhttp3/FormBody.kt
+++ b/okhttp/src/main/java/okhttp3/FormBody.kt
@@ -18,6 +18,7 @@ package okhttp3
 import okhttp3.HttpUrl.Companion.FORM_ENCODE_SET
 import okhttp3.HttpUrl.Companion.canonicalize
 import okhttp3.HttpUrl.Companion.percentDecode
+import okhttp3.MediaType.Companion.toMediaType
 import okhttp3.internal.toImmutableList
 import okio.Buffer
 import okio.BufferedSink
@@ -120,6 +121,6 @@ class FormBody internal constructor(
   }
 
   companion object {
-    private val CONTENT_TYPE: MediaType = MediaType.get("application/x-www-form-urlencoded")
+    private val CONTENT_TYPE: MediaType = "application/x-www-form-urlencoded".toMediaType()
   }
 }
diff --git a/okhttp/src/main/java/okhttp3/MediaType.kt b/okhttp/src/main/java/okhttp3/MediaType.kt
index e9944c891..4cc66fcdd 100644
--- a/okhttp/src/main/java/okhttp3/MediaType.kt
+++ b/okhttp/src/main/java/okhttp3/MediaType.kt
@@ -85,24 +85,25 @@ class MediaType private constructor(
     private val PARAMETER = Pattern.compile(";\\s*(?:$TOKEN=(?:$TOKEN|$QUOTED))?")
 
     /**
-     * Returns a media type for [string].
+     * Returns a media type for this string.
      *
-     * @throws IllegalArgumentException if [string] is not a well-formed media type.
+     * @throws IllegalArgumentException if this is not a well-formed media type.
      */
     @JvmStatic
-    fun get(string: String): MediaType {
-      val typeSubtype = TYPE_SUBTYPE.matcher(string)
-      require(typeSubtype.lookingAt()) { "No subtype found for: \"$string\"" }
+    @JvmName("get")
+    fun String.toMediaType(): MediaType {
+      val typeSubtype = TYPE_SUBTYPE.matcher(this)
+      require(typeSubtype.lookingAt()) { "No subtype found for: \"$this\"" }
       val type = typeSubtype.group(1).toLowerCase(Locale.US)
       val subtype = typeSubtype.group(2).toLowerCase(Locale.US)
 
       var charset: String? = null
-      val parameter = PARAMETER.matcher(string)
+      val parameter = PARAMETER.matcher(this)
       var s = typeSubtype.end()
-      while (s < string.length) {
-        parameter.region(s, string.length)
+      while (s < length) {
+        parameter.region(s, length)
         require(parameter.lookingAt()) {
-          "Parameter is not formatted correctly: \"${string.substring(s)}\" for: \"$string\""
+          "Parameter is not formatted correctly: \"${substring(s)}\" for: \"$this\""
         }
 
         val name = parameter.group(1)
@@ -124,23 +125,42 @@ class MediaType private constructor(
           else -> token
         }
         require(charset == null || charsetParameter.equals(charset, ignoreCase = true)) {
-          "Multiple charsets defined: \"$charset\" and: \"$charsetParameter\" for: \"$string\""
+          "Multiple charsets defined: \"$charset\" and: \"$charsetParameter\" for: \"$this\""
         }
         charset = charsetParameter
         s = parameter.end()
       }
 
-      return MediaType(string, type, subtype, charset)
+      return MediaType(this, type, subtype, charset)
     }
 
-    /** Returns a media type for [string], or null if [string] is not a well-formed media type. */
+    /** Returns a media type for this, or null if this is not a well-formed media type. */
     @JvmStatic
-    fun parse(string: String): MediaType? {
+    @JvmName("parse")
+    fun String.toMediaTypeOrNull(): MediaType? {
       return try {
-        get(string)
+        toMediaType()
       } catch (_: IllegalArgumentException) {
         null
       }
     }
+
+    @JvmName("-deprecated_get")
+    @Deprecated(
+        message = "moved to extension function",
+        replaceWith = ReplaceWith(
+            expression = "mediaType.toMediaType()",
+            imports = ["okhttp3.MediaType.Companion.toMediaType"]),
+        level = DeprecationLevel.WARNING)
+    fun get(mediaType: String): MediaType = mediaType.toMediaType()
+
+    @JvmName("-deprecated_parse")
+    @Deprecated(
+        message = "moved to extension function",
+        replaceWith = ReplaceWith(
+            expression = "mediaType.toMediaTypeOrNull()",
+            imports = ["okhttp3.MediaType.Companion.toMediaTypeOrNull"]),
+        level = DeprecationLevel.WARNING)
+    fun parse(mediaType: String): MediaType? = mediaType.toMediaTypeOrNull()
   }
 }
diff --git a/okhttp/src/main/java/okhttp3/MultipartBody.kt b/okhttp/src/main/java/okhttp3/MultipartBody.kt
index 19e4f8fd9..5c70a7934 100644
--- a/okhttp/src/main/java/okhttp3/MultipartBody.kt
+++ b/okhttp/src/main/java/okhttp3/MultipartBody.kt
@@ -15,7 +15,7 @@
  */
 package okhttp3
 
-import okhttp3.RequestBody.Companion.toRequestBody
+import okhttp3.MediaType.Companion.toMediaType
 import okhttp3.internal.toImmutableList
 import okio.Buffer
 import okio.BufferedSink
@@ -34,7 +34,7 @@ class MultipartBody internal constructor(
   @get:JvmName("type") val type: MediaType,
   @get:JvmName("parts") val parts: List<Part>
 ) : RequestBody() {
-  private val contentType: MediaType = MediaType.get("$type; boundary=$boundary")
+  private val contentType: MediaType = "$type; boundary=$boundary".toMediaType()
   private var contentLength = -1L
 
   @get:JvmName("boundary") val boundary: String
@@ -280,7 +280,7 @@ class MultipartBody internal constructor(
      * does not recognize must be treated as being of subtype "mixed".
      */
     @JvmField
-    val MIXED = MediaType.get("multipart/mixed")
+    val MIXED = "multipart/mixed".toMediaType()
 
     /**
      * The "multipart/alternative" type is syntactically identical to "multipart/mixed", but the
@@ -288,7 +288,7 @@ class MultipartBody internal constructor(
      * the same information.
      */
     @JvmField
-    val ALTERNATIVE = MediaType.get("multipart/alternative")
+    val ALTERNATIVE = "multipart/alternative".toMediaType()
 
     /**
      * This type is syntactically identical to "multipart/mixed", but the semantics are different.
@@ -296,14 +296,14 @@ class MultipartBody internal constructor(
      * "text/plain" to "message/rfc822".
      */
     @JvmField
-    val DIGEST = MediaType.get("multipart/digest")
+    val DIGEST = "multipart/digest".toMediaType()
 
     /**
      * This type is syntactically identical to "multipart/mixed", but the semantics are different.
      * In particular, in a parallel entity, the order of body parts is not significant.
      */
     @JvmField
-    val PARALLEL = MediaType.get("multipart/parallel")
+    val PARALLEL = "multipart/parallel".toMediaType()
 
     /**
      * The media-type multipart/form-data follows the rules of all multipart MIME data streams as
@@ -311,7 +311,7 @@ class MultipartBody internal constructor(
      * fills out the form. Each field has a name. Within a given form, the names are unique.
      */
     @JvmField
-    val FORM = MediaType.get("multipart/form-data")
+    val FORM = "multipart/form-data".toMediaType()
 
     private val COLONSPACE = byteArrayOf(':'.toByte(), ' '.toByte())
     private val CRLF = byteArrayOf('\r'.toByte(), '\n'.toByte())
diff --git a/okhttp/src/main/java/okhttp3/RequestBody.kt b/okhttp/src/main/java/okhttp3/RequestBody.kt
index c7a4c2eb0..f2d38e9ad 100644
--- a/okhttp/src/main/java/okhttp3/RequestBody.kt
+++ b/okhttp/src/main/java/okhttp3/RequestBody.kt
@@ -15,6 +15,7 @@
  */
 package okhttp3
 
+import okhttp3.MediaType.Companion.toMediaTypeOrNull
 import okhttp3.internal.checkOffsetAndCount
 import okio.BufferedSink
 import okio.ByteString
@@ -103,7 +104,7 @@ abstract class RequestBody {
         val resolvedCharset = contentType.charset()
         if (resolvedCharset == null) {
           charset = UTF_8
-          finalContentType = MediaType.parse("$contentType; charset=utf-8")
+          finalContentType = "$contentType; charset=utf-8".toMediaTypeOrNull()
         } else {
           charset = resolvedCharset
         }
diff --git a/okhttp/src/main/java/okhttp3/ResponseBody.kt b/okhttp/src/main/java/okhttp3/ResponseBody.kt
index e3aeee6aa..526ceb5dc 100644
--- a/okhttp/src/main/java/okhttp3/ResponseBody.kt
+++ b/okhttp/src/main/java/okhttp3/ResponseBody.kt
@@ -15,6 +15,7 @@
  */
 package okhttp3
 
+import okhttp3.MediaType.Companion.toMediaTypeOrNull
 import okhttp3.internal.closeQuietly
 import okhttp3.internal.readBomAsCharset
 import okio.Buffer
@@ -216,7 +217,7 @@ abstract class ResponseBody : Closeable {
         val resolvedCharset = contentType.charset()
         if (resolvedCharset == null) {
           charset = UTF_8
-          finalContentType = MediaType.parse("$contentType; charset=utf-8")
+          finalContentType = "$contentType; charset=utf-8".toMediaTypeOrNull()
         } else {
           charset = resolvedCharset
         }
diff --git a/okhttp/src/main/java/okhttp3/internal/http/RealResponseBody.kt b/okhttp/src/main/java/okhttp3/internal/http/RealResponseBody.kt
index f27f56be6..78a0d7398 100644
--- a/okhttp/src/main/java/okhttp3/internal/http/RealResponseBody.kt
+++ b/okhttp/src/main/java/okhttp3/internal/http/RealResponseBody.kt
@@ -16,6 +16,7 @@
 package okhttp3.internal.http
 
 import okhttp3.MediaType
+import okhttp3.MediaType.Companion.toMediaTypeOrNull
 import okhttp3.ResponseBody
 import okio.BufferedSource
 
@@ -31,13 +32,7 @@ class RealResponseBody(
 
   override fun contentLength(): Long = contentLength
 
-  override fun contentType(): MediaType? {
-    return if (contentTypeString != null) {
-      MediaType.parse(contentTypeString)
-    } else {
-      null
-    }
-  }
+  override fun contentType(): MediaType? = contentTypeString?.toMediaTypeOrNull()
 
   override fun source(): BufferedSource = source
 }
diff --git a/okhttp/src/main/java/okhttp3/internal/platform/Jdk8WithJettyBootPlatform.kt b/okhttp/src/main/java/okhttp3/internal/platform/Jdk8WithJettyBootPlatform.kt
index 0079045c9..92e8d1c96 100644
--- a/okhttp/src/main/java/okhttp3/internal/platform/Jdk8WithJettyBootPlatform.kt
+++ b/okhttp/src/main/java/okhttp3/internal/platform/Jdk8WithJettyBootPlatform.kt
@@ -129,7 +129,7 @@ class Jdk8WithJettyBootPlatform(
         // 1.8, 9, 10, 11, 12 etc
         val version = jvmVersion.toInt()
         if (version >= 9) return null
-      } catch (nfe: NumberFormatException) {
+      } catch (_: NumberFormatException) {
         // expected on >= JDK 9
       }