diff --git a/README.md b/README.md
index b446980..6827880 100644
--- a/README.md
+++ b/README.md
@@ -21,8 +21,8 @@ No one has agreed on a standard way of representing lon/lat. This is a small nor
 
 #### Table of Contents
 
--   [input](#input)
--   [InvalidCoordinateException](#invalidcoordinateexception)
+-   [lonlat.types.input](#lonlattypesinput)
+-   [lonlat.types.InvalidCoordinateException](#lonlattypesinvalidcoordinateexception)
 -   [conveyal/lonlat](#conveyallonlat)
     -   [fromCoordinates](#fromcoordinates)
     -   [fromLatlng](#fromlatlng)
@@ -34,9 +34,9 @@ No one has agreed on a standard way of representing lon/lat. This is a small nor
     -   [toLeaflet](#toleaflet)
     -   [toPoint](#topoint)
     -   [toString](#tostring)
--   [lonlat](#lonlat)
+-   [lonlat.types.output](#lonlattypesoutput)
 
-### input
+### lonlat.types.input
 
 (type)
 
@@ -57,7 +57,7 @@ Type: ([Array](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference
 
 -   `unknown`  
 
-### InvalidCoordinateException
+### lonlat.types.InvalidCoordinateException
 
 (exception type)
 
@@ -75,7 +75,7 @@ Parse an unknown type of input.
 
 **Parameters**
 
--   `unknown` **[input](#input)** 
+-   `unknown` **[lonlat.types.input](#lonlattypesinput)** 
 
 **Examples**
 
@@ -104,9 +104,9 @@ position = lonlat({})                      // Error: Invalid latitude value: und
 position = lonlat(null)                    // Error: Value must not be null or undefined
 ```
 
--   Throws **[InvalidCoordinateException](#invalidcoordinateexception)** 
+-   Throws **[lonlat.types.InvalidCoordinateException](#lonlattypesinvalidcoordinateexception)** 
 
-Returns **[lonlat](#lonlat)** 
+Returns **[lonlat.types.output](#lonlattypesoutput)** 
 
 #### fromCoordinates
 
@@ -127,9 +127,9 @@ var position = lonlat.fromCoordinates([12, 34])   // { lon: 12, lat: 34 }
 position = lonlat.fromGeoJSON([12, 34])           // { lon: 12, lat: 34 }
 ```
 
--   Throws **[InvalidCoordinateException](#invalidcoordinateexception)** 
+-   Throws **[lonlat.types.InvalidCoordinateException](#lonlattypesinvalidcoordinateexception)** 
 
-Returns **[lonlat](#lonlat)** 
+Returns **[lonlat.types.output](#lonlattypesoutput)** 
 
 #### fromLatlng
 
@@ -150,9 +150,9 @@ var position = lonlat.fromLatlng({ longitude: 12, latitude: 34 })   // { lon: 12
 position = lonlat.fromLeaflet({ lng: 12, lat: 34 })                 // { lon: 12, lat: 34 }
 ```
 
--   Throws **[InvalidCoordinateException](#invalidcoordinateexception)** 
+-   Throws **[lonlat.types.InvalidCoordinateException](#lonlattypesinvalidcoordinateexception)** 
 
-Returns **[lonlat](#lonlat)** 
+Returns **[lonlat.types.output](#lonlattypesoutput)** 
 
 #### fromPoint
 
@@ -171,9 +171,9 @@ var lonlat = require('@conveyal/lonlat')
 var position = lonlat.fromPoint({ x: 12, y: 34 })   // { lon: 12, lat: 34 }
 ```
 
--   Throws **[InvalidCoordinateException](#invalidcoordinateexception)** 
+-   Throws **[lonlat.types.InvalidCoordinateException](#lonlattypesinvalidcoordinateexception)** 
 
-Returns **[lonlat](#lonlat)** 
+Returns **[lonlat.types.output](#lonlattypesoutput)** 
 
 #### fromString
 
@@ -182,18 +182,20 @@ Tries to parse from a string.
 **Parameters**
 
 -   `str` **[string](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String)** A string in the format: `longitude,latitude`
+-   `latIsFirst` **[boolean](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Boolean)?** Whether or not the first value is latitude. (optional, default `false`)
 
 **Examples**
 
 ```javascript
 var lonlat = require('@conveyal/lonlat')
 
-var position = lonlat.fromString('12,34')   // { lon: 12, lat: 34 }
+var position = lonlat.fromString('12,34')        // { lon: 12, lat: 34 }
+var position = lonlat.fromString('12,34', true)  // { lon: 34, lat: 12 }
 ```
 
--   Throws **[InvalidCoordinateException](#invalidcoordinateexception)** 
+-   Throws **[lonlat.types.InvalidCoordinateException](#lonlattypesinvalidcoordinateexception)** 
 
-Returns **[lonlat](#lonlat)** 
+Returns **[lonlat.types.output](#lonlattypesoutput)** 
 
 #### isEqual
 
@@ -201,9 +203,9 @@ Determine if two inputs are equal to each other
 
 **Parameters**
 
--   `lonlat1` **[input](#input)** 
--   `lonlat2` **[input](#input)** 
--   `epsilon` **[number](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number)?** The maximum acceptable deviation to be considered equal.  Default = 0
+-   `lonlat1` **input** 
+-   `lonlat2` **input** 
+-   `epsilon` **[number](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number)?** The maximum acceptable deviation to be considered equal. (optional, default `0`)
 
 **Examples**
 
@@ -213,7 +215,7 @@ var lonlat = require('@conveyal/lonlat')
 var isEqual = lonlat.isEqual('12,34', [12, 34])   // true
 ```
 
--   Throws **[InvalidCoordinateException](#invalidcoordinateexception)** 
+-   Throws **[lonlat.types.InvalidCoordinateException](#lonlattypesinvalidcoordinateexception)** 
 
 Returns **[boolean](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** 
 
@@ -221,8 +223,8 @@ Returns **[boolean](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe
 
 **Parameters**
 
--   `input` **[input](#input)** 
--   `fixed` **[number](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number)?** The number of decimal places to round to.
+-   `input` **input** 
+-   `fixed` **[number](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number)?** The number of decimal places to round to. (optional, default `5`)
 
 **Examples**
 
@@ -232,7 +234,7 @@ var lonlat = require('@conveyal/lonlat')
 var pretty = lonlat.print('12.345678,34')   // '12.34568, 34.00000'
 ```
 
--   Throws **[InvalidCoordinateException](#invalidcoordinateexception)** 
+-   Throws **[lonlat.types.InvalidCoordinateException](#lonlattypesinvalidcoordinateexception)** 
 
 Returns **[string](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String)** A string with in the format `longitude,latitude` rounded to
                            the number of decimal places as specified by `fixed`
@@ -245,7 +247,7 @@ Translates to a coordinate array.
 
 **Parameters**
 
--   `input` **[input](#input)** 
+-   `input` **[lonlat.types.input](#lonlattypesinput)** 
 
 **Examples**
 
@@ -255,7 +257,7 @@ var lonlat = require('@conveyal/lonlat')
 var coords = lonlat.toCoordinates('12,34')   // [12, 34]
 ```
 
--   Throws **[InvalidCoordinateException](#invalidcoordinateexception)** 
+-   Throws **[lonlat.types.InvalidCoordinateException](#lonlattypesinvalidcoordinateexception)** 
 
 Returns **[Array](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array)** An array in the format [longitude, latitude]
 
@@ -266,7 +268,7 @@ This function requires Leaflet to be installed as a global variable `L` in the w
 
 **Parameters**
 
--   `input` **[input](#input)** 
+-   `input` **[lonlat.types.input](#lonlattypesinput)** 
 
 **Examples**
 
@@ -276,7 +278,7 @@ var lonlat = require('@conveyal/lonlat')
 var position = lonlat.toLeaflet({ lat: 12, long: 34 })   // Leaflet LatLng object
 ```
 
--   Throws **[InvalidCoordinateException](#invalidcoordinateexception)** 
+-   Throws **[lonlat.types.InvalidCoordinateException](#lonlattypesinvalidcoordinateexception)** 
 
 Returns **[Object](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object)** A Leaflet LatLng object
 
@@ -286,7 +288,7 @@ Translates to point Object.
 
 **Parameters**
 
--   `input` **[input](#input)** 
+-   `input` **[lonlat.types.input](#lonlattypesinput)** 
 
 **Examples**
 
@@ -296,7 +298,7 @@ var lonlat = require('@conveyal/lonlat')
 var point = lonlat.toPoint('12,34')   // { x: 12, y: 34 }
 ```
 
--   Throws **[InvalidCoordinateException](#invalidcoordinateexception)** 
+-   Throws **[lonlat.types.InvalidCoordinateException](#lonlattypesinvalidcoordinateexception)** 
 
 Returns **[Object](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object)** An object with `x` and `y` attributes representing latitude and longitude respectively
 
@@ -306,7 +308,7 @@ Translates to coordinate string.
 
 **Parameters**
 
--   `input` **[input](#input)** 
+-   `input` **[lonlat.types.input](#lonlattypesinput)** 
 
 **Examples**
 
@@ -316,11 +318,11 @@ var lonlat = require('@conveyal/lonlat')
 var str = lonlat.toString({ lat: 12, longitude: 34 })   // '34,12'
 ```
 
--   Throws **[InvalidCoordinateException](#invalidcoordinateexception)** 
+-   Throws **[lonlat.types.InvalidCoordinateException](#lonlattypesinvalidcoordinateexception)** 
 
 Returns **[string](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String)** A string in the format 'longitude,latitude'
 
-### lonlat
+### lonlat.types.output
 
 (type)
 
diff --git a/index.js b/index.js
index 2e5d313..f2063d3 100644
--- a/index.js
+++ b/index.js
@@ -10,14 +10,14 @@
  *   The properties can be named various things.
  *   For longitude any of the following are valid: `lon`, `lng` or `longitude`
  *   For latitude any of the following are valid: `lat` or `latitude`
- * @typedef {Array|string|Object} input
+ * @typedef {Array|string|Object} lonlat.types.input
  */
 
 /**
  * (type)
  *
  * Standardized lon/lat object.
- * @typedef {Object} lonlat
+ * @typedef {Object} lonlat.types.output
  * @property {number} lat
  * @property {number} lon
  */
@@ -26,16 +26,16 @@
  * (exception type)
  *
  * An error that is thrown upon providing invalid coordinates.
- * @typedef {Error} InvalidCoordinateException
+ * @typedef {Error} lonlat.types.InvalidCoordinateException
  */
 
 /**
  * Parse an unknown type of input.
  *
  * @module conveyal/lonlat
- * @param {input} unknown
- * @return {lonlat}
- * @throws {InvalidCoordinateException}
+ * @param {lonlat.types.input} unknown
+ * @return {lonlat.types.output}
+ * @throws {lonlat.types.InvalidCoordinateException}
  * @example
  * var lonlat = require('@conveyal/lonlat')
 
@@ -76,8 +76,8 @@ module.exports = normalize
  *
  * @memberof conveyal/lonlat
  * @param  {Array} coordinates  An array in the format: [longitude, latitude]
- * @return {lonlat}
- * @throws {InvalidCoordinateException}
+ * @return {lonlat.types.output}
+ * @throws {lonlat.types.InvalidCoordinateException}
  * @example
  * var lonlat = require('@conveyal/lonlat')
 
@@ -95,8 +95,8 @@ module.exports.fromCoordinates = module.exports.fromGeoJSON = fromCoordinates
  * Tries to parse from an object.
  *
  * @param  {Object} lonlat  An object with a `lon`, `lng` or `longitude` attribute and a `lat` or `latitude` attribute
- * @return {lonlat}
- * @throws {InvalidCoordinateException}
+ * @return {lonlat.types.output}
+ * @throws {lonlat.types.InvalidCoordinateException}
  * @example
  * var lonlat = require('@conveyal/lonlat')
 
@@ -113,8 +113,8 @@ module.exports.fromLatlng = module.exports.fromLeaflet = function fromLatlng (lo
  * @memberof conveyal/lonlat
  * @param  {Object} point  An object with a `x` attribute representing `longitude`
  *                         and a `y` attribute representing `latitude`
- * @return {lonlat}
- * @throws {InvalidCoordinateException}
+ * @return {lonlat.types.output}
+ * @throws {lonlat.types.InvalidCoordinateException}
  * @example
  * var lonlat = require('@conveyal/lonlat')
 
@@ -129,17 +129,21 @@ module.exports.fromPoint = fromPoint
  * Tries to parse from a string.
  *
  * @memberof conveyal/lonlat
- * @param  {string} str A string in the format: `longitude,latitude`
- * @return {lonlat}
- * @throws {InvalidCoordinateException}
+ * @param  {string} str                 A string in the format: `longitude,latitude`
+ * @param  {boolean} [latIsFirst=false] Whether or not the first value is latitude.
+ * @return {lonlat.types.output}
+ * @throws {lonlat.types.InvalidCoordinateException}
  * @example
  * var lonlat = require('@conveyal/lonlat')
 
- var position = lonlat.fromString('12,34')   // { lon: 12, lat: 34 }
+ var position = lonlat.fromString('12,34')        // { lon: 12, lat: 34 }
+ var position = lonlat.fromString('12,34', true)  // { lon: 34, lat: 12 }
  */
-function fromString (str) {
+function fromString (str, latIsFirst) {
   var arr = str.split(',')
-  return floatize({lon: arr[0], lat: arr[1]})
+  return latIsFirst
+    ? floatize({lat: arr[0], lon: arr[1]})
+    : floatize({lon: arr[0], lat: arr[1]})
 }
 module.exports.fromString = fromString
 
@@ -148,9 +152,9 @@ module.exports.fromString = fromString
  *
  * @param  {input}  lonlat1
  * @param  {input}  lonlat2
- * @param  {number} [epsilon] The maximum acceptable deviation to be considered equal.  Default = 0
+ * @param  {number} [epsilon=0] The maximum acceptable deviation to be considered equal.
  * @return {boolean}
- * @throws {InvalidCoordinateException}
+ * @throws {lonlat.types.InvalidCoordinateException}
  * @example
  * var lonlat = require('@conveyal/lonlat')
 
@@ -165,10 +169,10 @@ module.exports.isEqual = function (lonlat1, lonlat2, epsilon) {
 
 /**
  * @param  {input} input
- * @param  {number} [fixed] The number of decimal places to round to.
- * @return {string}         A string with in the format `longitude,latitude` rounded to
+ * @param  {number} [fixed=5] The number of decimal places to round to.
+ * @return {string}           A string with in the format `longitude,latitude` rounded to
  *                            the number of decimal places as specified by `fixed`
- * @throws {InvalidCoordinateException}
+ * @throws {lonlat.types.InvalidCoordinateException}
  * @example
  * var lonlat = require('@conveyal/lonlat')
 
@@ -184,9 +188,9 @@ module.exports.print = function print (input, fixed) {
  *
  * Translates to a coordinate array.
  *
- * @param {input} input
+ * @param {lonlat.types.input} input
  * @return {Array}      An array in the format [longitude, latitude]
- * @throws {InvalidCoordinateException}
+ * @throws {lonlat.types.InvalidCoordinateException}
  * @example
  * var lonlat = require('@conveyal/lonlat')
 
@@ -201,9 +205,9 @@ module.exports.toCoordinates = module.exports.toGeoJSON = function toCoordinates
  * Translates to {@link http://leafletjs.com/reference-1.0.3.html#latlng|Leaflet LatLng} object.
  * This function requires Leaflet to be installed as a global variable `L` in the window environment.
  *
- * @param {input} input
+ * @param {lonlat.types.input} input
  * @return {Object}      A Leaflet LatLng object
- * @throws {InvalidCoordinateException}
+ * @throws {lonlat.types.InvalidCoordinateException}
  * @example
  * var lonlat = require('@conveyal/lonlat')
 
@@ -218,9 +222,9 @@ module.exports.toLeaflet = function toLeaflet (input) {
 /**
  * Translates to point Object.
  *
- * @param {input} input
+ * @param {lonlat.types.input} input
  * @return {Object}      An object with `x` and `y` attributes representing latitude and longitude respectively
- * @throws {InvalidCoordinateException}
+ * @throws {lonlat.types.InvalidCoordinateException}
  * @example
  * var lonlat = require('@conveyal/lonlat')
 
@@ -234,9 +238,9 @@ module.exports.toPoint = function toPoint (input) {
 /**
  * Translates to coordinate string.
  *
- * @param {input} input
+ * @param {lonlat.types.input} input
  * @return {string}     A string in the format 'longitude,latitude'
- * @throws {InvalidCoordinateException}
+ * @throws {lonlat.types.InvalidCoordinateException}
  * @example
  * var lonlat = require('@conveyal/lonlat')
 
diff --git a/index.test.js b/index.test.js
index 52428fc..d6444de 100644
--- a/index.test.js
+++ b/index.test.js
@@ -8,6 +8,7 @@ const lonlat = {lon, lat}
 const point = {x: lon, y: lat}
 const coordinates = [lon, lat]
 const str = `${lon},${lat}`
+const strLatFirst = `${lat},${lon}`
 const latlng = {lat, lng: lon}
 
 describe('lonlat', () => {
@@ -92,7 +93,10 @@ describe('lonlat', () => {
       description: 'Object with x and y keys'
     }, {
       calculated: ll.fromString(str),
-      description: 'String with comma separating lon and lat'
+      description: 'String with comma separating lon and lat, respectively'
+    }, {
+      calculated: ll.fromString(strLatFirst, true),
+      description: 'String with comma separating lat and lon, respectively'
     }]
 
     testCases.forEach((test) => {