diff --git a/lib/mempool/layout-browser.js b/lib/mempool/layout-browser.js
new file mode 100644
index 00000000..19f760fb
--- /dev/null
+++ b/lib/mempool/layout-browser.js
@@ -0,0 +1,33 @@
+/*!
+ * layout-browser.js - mempooldb layout for browser.
+ * Copyright (c) 2014-2017, Christopher Jeffrey (MIT License).
+ * https://github.com/bcoin-org/bcoin
+ */
+
+'use strict';
+
+var util = require('../utils/util');
+var pad32 = util.pad32;
+
+var layout = {
+  R: 'R',
+  e: function e(id, hash) {
+    return 'e' + pad32(id) + hex(hash);
+  }
+};
+
+/*
+ * Helpers
+ */
+
+function hex(hash) {
+  if (typeof hash !== 'string')
+    hash = hash.toString('hex');
+  return hash;
+}
+
+/*
+ * Expose
+ */
+
+module.exports = layout;
diff --git a/lib/mempool/layout.js b/lib/mempool/layout.js
new file mode 100644
index 00000000..0d489a94
--- /dev/null
+++ b/lib/mempool/layout.js
@@ -0,0 +1,40 @@
+/*!
+ * layout.js - mempool data layout for bcoin
+ * Copyright (c) 2014-2017, Christopher Jeffrey (MIT License).
+ * https://github.com/bcoin-org/bcoin
+ */
+
+'use strict';
+
+/*
+ * Database Layout:
+ *   R -> tip hash
+ *   e[id][hash] -> entry
+ */
+
+var layout = {
+  R: new Buffer([0x52]),
+  e: function e(id, hash) {
+    var key = new Buffer(37);
+    key[0] = 0x65;
+    key.writeUInt32BE(id, 1, true);
+    write(key, hash, 5);
+    return key;
+  }
+};
+
+/*
+ * Helpers
+ */
+
+function write(data, str, off) {
+  if (Buffer.isBuffer(str))
+    return str.copy(data, off);
+  data.write(str, off, 'hex');
+}
+
+/*
+ * Expose
+ */
+
+module.exports = layout;
diff --git a/lib/mempool/mempoolentry.js b/lib/mempool/mempoolentry.js
index 98347c75..0d6df75b 100644
--- a/lib/mempool/mempoolentry.js
+++ b/lib/mempool/mempoolentry.js
@@ -186,6 +186,65 @@ MempoolEntry.prototype.isFree = function isFree(height) {
   return priority > policy.FREE_THRESHOLD;
 };
 
+/**
+ * Get entry serialization size.
+ * @returns {Number}
+ */
+
+MempoolEntry.prototype.getSize = function getSize() {
+  return tx.getSize() + 37;
+};
+
+/**
+ * Serialize entry to a buffer.
+ * @returns {Buffer}
+ */
+
+MempoolEntry.prototype.toRaw = function toRaw() {
+  var bw = new StaticWriter(this.getSize());
+  bw.writeBytes(this.tx.toRaw());
+  bw.writeU32(this.height);
+  bw.writeU32(this.size);
+  bw.writeU32(this.sigops);
+  bw.writeDouble(this.priority);
+  bw.writeU32(this.fee);
+  bw.writeU32(this.ts);
+  bw.write64(this.value);
+  bw.writeU8(this.dependencies ? 1 : 0);
+  return bw.render();
+};
+
+/**
+ * Inject properties from serialized data.
+ * @private
+ * @param {Buffer} data
+ * @returns {MempoolEntry}
+ */
+
+MempoolEntry.prototype.fromRaw = function fromRaw(data) {
+  var br = new BufferReader(data);
+  this.tx = TX.fromReader(br);
+  this.height = br.readU32();
+  this.size = br.readU32();
+  this.sigops = br.readU32();
+  this.priority = br.readDouble();
+  this.fee = br.readU32();
+  this.ts = br.readU32();
+  this.value = br.read64();
+  this.dependencies = br.readU8() === 1;
+  return this;
+};
+
+/**
+ * Instantiate entry from serialized data.
+ * @param {Buffer} data
+ * @returns {MempoolEntry}
+ */
+
+MempoolEntry.fromRaw = function fromRaw(data) {
+  return new MempoolEntry().fromRaw(data);
+};
+
 /*
  * Expose
  */