diff --git a/benchmarks/pom.xml b/benchmarks/pom.xml
index 14d93eeefd8b..960296b11810 100644
--- a/benchmarks/pom.xml
+++ b/benchmarks/pom.xml
@@ -13,6 +13,11 @@
   <name>Benchmarks</name>
 
   <dependencies>
+    <dependency>
+      <groupId>com.google.caliper</groupId>
+      <artifactId>caliper</artifactId>
+      <version>1.0-beta-1</version>
+    </dependency>
     <dependency>
       <groupId>com.squareup.okhttp</groupId>
       <artifactId>okhttp</artifactId>
@@ -51,5 +56,11 @@
       <artifactId>netty-codec-http</artifactId>
       <version>4.0.15.Final</version>
     </dependency>
+    <!-- Netty needs this if gzip is enabled. -->
+    <dependency>
+      <groupId>com.jcraft</groupId>
+      <artifactId>jzlib</artifactId>
+      <version>1.1.2</version>
+    </dependency>
   </dependencies>
 </project>
diff --git a/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/ApacheHttpClient.java b/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/ApacheHttpClient.java
index cd2cba31cff9..cb8e719111c4 100644
--- a/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/ApacheHttpClient.java
+++ b/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/ApacheHttpClient.java
@@ -61,7 +61,6 @@ public ApacheHttpClientRequest(URL url) {
     }
 
     public void run() {
-      byte[] buffer = new byte[1024];
       long start = System.nanoTime();
       try {
         HttpResponse response = client.execute(new HttpGet(url.toString()));
@@ -71,12 +70,7 @@ public void run() {
           in = new GZIPInputStream(in);
         }
 
-        // Consume the response body.
-        int total = 0;
-        for (int count; (count = in.read(buffer)) != -1; ) {
-          total += count;
-        }
-        in.close();
+        long total = readAllAndClose(in);
         long finish = System.nanoTime();
 
         if (VERBOSE) {
diff --git a/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/Benchmark.java b/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/Benchmark.java
index 16bd063508a5..3b2b5e59dfb9 100644
--- a/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/Benchmark.java
+++ b/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/Benchmark.java
@@ -15,6 +15,9 @@
  */
 package com.squareup.okhttp.benchmarks;
 
+import com.google.caliper.Param;
+import com.google.caliper.model.ArbitraryMeasurement;
+import com.google.caliper.runner.CaliperMain;
 import com.squareup.okhttp.Protocol;
 import com.squareup.okhttp.internal.SslContextBuilder;
 import com.squareup.okhttp.mockwebserver.Dispatcher;
@@ -40,41 +43,57 @@
  * It uses a local connection to a MockWebServer to measure how many identical
  * requests per second can be carried over a fixed number of threads.
  */
-public class Benchmark {
+public class Benchmark extends com.google.caliper.Benchmark {
   private static final int NUM_REPORTS = 10;
+  private static final boolean VERBOSE = false;
+
   private final Random random = new Random(0);
 
   /** Which client to run.*/
-  HttpClient httpClient = new NettyHttpClient();
+  @Param
+  Client client;
 
   /** How many concurrent requests to execute. */
-  int concurrencyLevel = 10;
+  @Param({ "1", "10" })
+  int concurrencyLevel;
 
   /** True to use TLS. */
   // TODO: compare different ciphers?
-  boolean tls = false;
+  @Param
+  boolean tls;
 
   /** True to use gzip content-encoding for the response body. */
-  boolean gzip = false;
+  @Param
+  boolean gzip;
 
   /** Don't combine chunked with SPDY_3 or HTTP_2; that's not allowed. */
-  boolean chunked = false;
+  @Param
+  boolean chunked;
 
   /** The size of the HTTP response body, in uncompressed bytes. */
-  int bodyByteCount = 1024 * 1024;
+  @Param({ "128", "1048576" })
+  int bodyByteCount;
 
   /** How many additional headers were included, beyond the built-in ones. */
-  int headerCount = 20;
+  @Param({ "0", "20" })
+  int headerCount;
 
   /** Which ALPN/NPN protocols are in use. Only useful with TLS. */
   List<Protocol> protocols = Arrays.asList(Protocol.HTTP_11);
 
-  public static void main(String[] args) throws Exception {
-    new Benchmark().run();
+  public static void main(String[] args) {
+    List<String> allArgs = new ArrayList<String>();
+    allArgs.add("--instrument");
+    allArgs.add("arbitrary");
+    allArgs.addAll(Arrays.asList(args));
+
+    CaliperMain.main(Benchmark.class, allArgs.toArray(new String[allArgs.size()]));
   }
 
-  public void run() throws Exception {
-    System.out.println(toString());
+  @ArbitraryMeasurement(description = "requests per second")
+  public double run() throws Exception {
+    if (VERBOSE) System.out.println(toString());
+    HttpClient httpClient = client.create();
 
     // Prepare the client & server
     httpClient.prepare(this);
@@ -85,6 +104,7 @@ public void run() throws Exception {
     long reportStart = System.nanoTime();
     long reportPeriod = TimeUnit.SECONDS.toNanos(1);
     int reports = 0;
+    double best = 0.0;
 
     // Run until we've printed enough reports.
     while (reports < NUM_REPORTS) {
@@ -93,7 +113,10 @@ public void run() throws Exception {
       double reportDuration = now - reportStart;
       if (reportDuration > reportPeriod) {
         double requestsPerSecond = requestCount / reportDuration * TimeUnit.SECONDS.toNanos(1);
-        System.out.println(String.format("Requests per second: %.1f", requestsPerSecond));
+        if (VERBOSE) {
+          System.out.println(String.format("Requests per second: %.1f", requestsPerSecond));
+        }
+        best = Math.max(best, requestsPerSecond);
         requestCount = 0;
         reportStart = now;
         reports++;
@@ -108,6 +131,8 @@ public void run() throws Exception {
       // The job queue is full. Take a break.
       sleep(10);
     }
+
+    return best;
   }
 
   @Override public String toString() {
@@ -117,10 +142,8 @@ public void run() throws Exception {
     if (chunked) modifiers.add("chunked");
     modifiers.addAll(protocols);
 
-    return String.format("%s %s\n"
-        + "bodyByteCount=%s headerCount=%s concurrencyLevel=%s",
-        httpClient.getClass().getSimpleName(), modifiers,
-        bodyByteCount, headerCount, concurrencyLevel);
+    return String.format("%s %s\nbodyByteCount=%s headerCount=%s concurrencyLevel=%s",
+        client, modifiers, bodyByteCount, headerCount, concurrencyLevel);
   }
 
   private void sleep(int millis) {
diff --git a/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/Client.java b/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/Client.java
new file mode 100644
index 000000000000..0f076a610d14
--- /dev/null
+++ b/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/Client.java
@@ -0,0 +1,44 @@
+/*
+ * Copyright (C) 2014 Square, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.squareup.okhttp.benchmarks;
+
+enum Client {
+  OkHttp {
+    @Override HttpClient create() {
+      return new OkHttp();
+    }
+  },
+
+  Apache {
+    @Override HttpClient create() {
+      return new ApacheHttpClient();
+    }
+  },
+
+  UrlConnection {
+    @Override HttpClient create() {
+      return new UrlConnection();
+    }
+  },
+
+  Netty {
+    @Override HttpClient create() {
+      return new NettyHttpClient();
+    }
+  };
+
+  abstract HttpClient create();
+}
diff --git a/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/NettyHttpClient.java b/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/NettyHttpClient.java
index d5adec5a053b..c3b06512eb5d 100644
--- a/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/NettyHttpClient.java
+++ b/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/NettyHttpClient.java
@@ -48,7 +48,7 @@
 import javax.net.ssl.SSLEngine;
 
 /** Netty isn't an HTTP client, but it's almost one. */
-public class NettyHttpClient implements HttpClient {
+class NettyHttpClient implements HttpClient {
   private static final boolean VERBOSE = false;
 
   // Guarded by this. Real apps need more capable connection management.
diff --git a/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/OkHttp.java b/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/OkHttp.java
index 6fdb40e9acbb..03b9e3c6f10a 100644
--- a/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/OkHttp.java
+++ b/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/OkHttp.java
@@ -18,7 +18,6 @@
 import com.squareup.okhttp.OkHttpClient;
 import com.squareup.okhttp.internal.SslContextBuilder;
 import java.io.IOException;
-import java.io.InputStream;
 import java.net.HttpURLConnection;
 import java.net.URL;
 import java.util.concurrent.TimeUnit;
@@ -62,18 +61,10 @@ public OkHttpRequest(URL url) {
     }
 
     public void run() {
-      byte[] buffer = new byte[1024];
       long start = System.nanoTime();
       try {
         HttpURLConnection urlConnection = client.open(url);
-        InputStream in = urlConnection.getInputStream();
-
-        // Consume the response body.
-        int total = 0;
-        for (int count; (count = in.read(buffer)) != -1; ) {
-          total += count;
-        }
-        in.close();
+        long total = readAllAndClose(urlConnection.getInputStream());
         long finish = System.nanoTime();
 
         if (VERBOSE) {
diff --git a/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/SynchronousHttpClient.java b/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/SynchronousHttpClient.java
index 9a0851c7ff66..f4bb02c79b07 100644
--- a/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/SynchronousHttpClient.java
+++ b/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/SynchronousHttpClient.java
@@ -15,6 +15,8 @@
  */
 package com.squareup.okhttp.benchmarks;
 
+import java.io.IOException;
+import java.io.InputStream;
 import java.net.URL;
 import java.util.concurrent.LinkedBlockingQueue;
 import java.util.concurrent.ThreadPoolExecutor;
@@ -38,5 +40,15 @@ abstract class SynchronousHttpClient implements HttpClient {
     return executor.getQueue().size() < targetBacklog;
   }
 
+  protected long readAllAndClose(InputStream in) throws IOException {
+    byte[] buffer = new byte[1024];
+    long total = 0;
+    for (int count; (count = in.read(buffer)) != -1; ) {
+      total += count;
+    }
+    in.close();
+    return total;
+  }
+
   abstract Runnable request(URL url);
 }
diff --git a/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/UrlConnection.java b/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/UrlConnection.java
index a2c3f3af407e..53d2a4b9e9f3 100644
--- a/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/UrlConnection.java
+++ b/benchmarks/src/main/java/com/squareup/okhttp/benchmarks/UrlConnection.java
@@ -58,7 +58,6 @@ public UrlConnectionRequest(URL url) {
     }
 
     public void run() {
-      byte[] buffer = new byte[1024];
       long start = System.nanoTime();
       try {
         HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
@@ -67,12 +66,7 @@ public void run() {
           in = new GZIPInputStream(in);
         }
 
-        // Consume the response body.
-        int total = 0;
-        for (int count; (count = in.read(buffer)) != -1; ) {
-          total += count;
-        }
-        in.close();
+        long total = readAllAndClose(in);
         long finish = System.nanoTime();
 
         if (VERBOSE) {