diff --git a/README.md b/README.md
index b0914346..1035b42d 100644
--- a/README.md
+++ b/README.md
@@ -58,6 +58,7 @@ Parses command line arguments returning a simple mapping of keys and values.
   * `opts.narg`: specify that a key requires `n` arguments: `{narg: {x: 2}}`.
   * `opts.normalize`: `path.normalize()` will be applied to values set to this key.
   * `opts.string`: keys should be treated as strings (even if they resemble a number `-x 33`).
+  * `opts.number`: keys should be treated as numbers.
 
 **returns:**
 
diff --git a/index.js b/index.js
index 85ff3bc9..6317a378 100644
--- a/index.js
+++ b/index.js
@@ -26,6 +26,7 @@ function parse (args, opts) {
     arrays: {},
     bools: {},
     strings: {},
+    numbers: {},
     counts: {},
     normalize: {},
     configs: {},
@@ -45,6 +46,10 @@ function parse (args, opts) {
     flags.strings[key] = true
   })
 
+  ;[].concat(opts.number).filter(Boolean).forEach(function (key) {
+    flags.numbers[key] = true
+  })
+
   ;[].concat(opts.count).filter(Boolean).forEach(function (key) {
     flags.counts[key] = true
   })
@@ -522,6 +527,7 @@ function parse (args, opts) {
     var def = {
       boolean: true,
       string: '',
+      number: undefined,
       array: []
     }
 
@@ -533,12 +539,14 @@ function parse (args, opts) {
     var type = 'boolean'
 
     if (flags.strings && flags.strings[key]) type = 'string'
+    else if (flags.numbers && flags.numbers[key]) type = 'number'
     else if (flags.arrays && flags.arrays[key]) type = 'array'
 
     return type
   }
 
   function isNumber (x) {
+    if (flags.numbers && flags.numbers[x] && !isNaN(x)) return true
     if (!configuration['parse-numbers']) return false
     if (typeof x === 'number') return true
     if (/^0x[0-9a-f]+$/i.test(x)) return true
diff --git a/test/yargs-parser.js b/test/yargs-parser.js
index 43b95d99..1a5e55d0 100644
--- a/test/yargs-parser.js
+++ b/test/yargs-parser.js
@@ -176,6 +176,20 @@ describe('yargs-parser', function () {
     x.should.be.a('string').and.equal('56')
   })
 
+  it('should default numbers to undefined', function () {
+    var n = parser([ '-n' ], {
+      number: ['n']
+    }).n
+    expect(n).to.equal(undefined)
+  })
+
+  it('should default number to NaN if value is not a valid number', function () {
+    var n = parser([ '-n', 'string' ], {
+      number: ['n']
+    }).n
+    expect(n).to.equal(NaN)
+  })
+
   // Fixes: https://github.com/bcoe/yargs/issues/68
   it('should parse flag arguments with no right-hand-value as strings, if defined as strings', function () {
     var s = parser([ '-s' ], {