diff --git a/src/ol/format/Feature.js b/src/ol/format/Feature.js
index 542ad65cf4..6c770c93a9 100644
--- a/src/ol/format/Feature.js
+++ b/src/ol/format/Feature.js
@@ -10,8 +10,8 @@ import {get as getProjection, equivalent as equivalentProjection, transformExten
  * @typedef {Object} ReadOptions
  * @property {module:ol/proj~ProjectionLike} dataProjection Projection of the data we are reading.
  * If not provided, the projection will be derived from the data (where possible) or
- * the `defaultDataProjection` of the format is assigned (where set). If the projection
- * can not be derived from the data and if no `defaultDataProjection` is set for a format,
+ * the `dataProjection` of the format is assigned (where set). If the projection
+ * can not be derived from the data and if no `dataProjection` is set for a format,
  * the features will not be reprojected.
  * @property {module:ol/extent~Extent} extent Tile extent of the tile being read. This is only used and
  * required for {@link module:ol/format/MVT}.
@@ -24,8 +24,8 @@ import {get as getProjection, equivalent as equivalentProjection, transformExten
 /**
  * @typedef {Object} WriteOptions
  * @property {module:ol/proj~ProjectionLike} dataProjection Projection of the data we are writing.
- * If not provided, the `defaultDataProjection` of the format is assigned (where set).
- * If no `defaultDataProjection` is set for a format, the features will be returned
+ * If not provided, the `dataProjection` of the format is assigned (where set).
+ * If no `dataProjection` is set for a format, the features will be returned
  * in the `featureProjection`.
  * @property {module:ol/proj~ProjectionLike} featureProjection Projection of the feature geometries
  * that will be serialized by the format writer. If not provided, geometries are assumed
@@ -66,7 +66,7 @@ const FeatureFormat = function() {
    * @protected
    * @type {module:ol/proj/Projection}
    */
-  this.defaultDataProjection = null;
+  this.dataProjection = null;
 
   /**
    * @protected
@@ -98,7 +98,7 @@ FeatureFormat.prototype.getReadOptions = function(source, opt_options) {
 
 
 /**
- * Sets the `defaultDataProjection` on the options, if no `dataProjection`
+ * Sets the `dataProjection` on the options, if no `dataProjection`
  * is set.
  * @param {module:ol/format/Feature~WriteOptions|module:ol/format/Feature~ReadOptions|undefined} options
  *     Options.
@@ -108,7 +108,7 @@ FeatureFormat.prototype.getReadOptions = function(source, opt_options) {
  */
 FeatureFormat.prototype.adaptOptions = function(options) {
   return assign({
-    dataProjection: this.defaultDataProjection,
+    dataProjection: this.dataProjection,
     featureProjection: this.defaultFeatureProjection
   }, options);
 };
diff --git a/src/ol/format/GPX.js b/src/ol/format/GPX.js
index e9e23de5f6..3b4cdb4a85 100644
--- a/src/ol/format/GPX.js
+++ b/src/ol/format/GPX.js
@@ -52,7 +52,7 @@ const GPX = function(opt_options) {
   /**
    * @inheritDoc
    */
-  this.defaultDataProjection = getProjection('EPSG:4326');
+  this.dataProjection = getProjection('EPSG:4326');
 
   /**
    * @type {function(module:ol/Feature, Node)|undefined}
diff --git a/src/ol/format/GeoJSON.js b/src/ol/format/GeoJSON.js
index 77a789350a..b162ed1988 100644
--- a/src/ol/format/GeoJSON.js
+++ b/src/ol/format/GeoJSON.js
@@ -22,7 +22,7 @@ import {get as getProjection} from '../proj.js';
 
 /**
  * @typedef {Object} Options
- * @property {module:ol/proj~ProjectionLike} [defaultDataProjection='EPSG:4326'] Default data projection.
+ * @property {module:ol/proj~ProjectionLike} [dataProjection='EPSG:4326'] Default data projection.
  * @property {module:ol/proj~ProjectionLike} [featureProjection] Projection for features read or
  * written by the format.  Options passed to read or write methods will take precedence.
  * @property {string} [geometryName] Geometry name to use when creating features.
@@ -51,10 +51,9 @@ const GeoJSON = function(opt_options) {
   /**
    * @inheritDoc
    */
-  this.defaultDataProjection = getProjection(
-    options.defaultDataProjection ?
-      options.defaultDataProjection : 'EPSG:4326');
-
+  this.dataProjection = getProjection(
+    options.dataProjection ?
+      options.dataProjection : 'EPSG:4326');
 
   if (options.featureProjection) {
     this.defaultFeatureProjection = getProjection(options.featureProjection);
@@ -456,7 +455,7 @@ GeoJSON.prototype.readProjectionFromObject = function(object) {
       assert(false, 36); // Unknown SRS type
     }
   } else {
-    projection = this.defaultDataProjection;
+    projection = this.dataProjection;
   }
   return (
     /** @type {module:ol/proj/Projection} */ (projection)
diff --git a/src/ol/format/IGC.js b/src/ol/format/IGC.js
index 0e8eaf6194..b09d8a1bca 100644
--- a/src/ol/format/IGC.js
+++ b/src/ol/format/IGC.js
@@ -45,7 +45,7 @@ const IGC = function(opt_options) {
   /**
    * @inheritDoc
    */
-  this.defaultDataProjection = getProjection('EPSG:4326');
+  this.dataProjection = getProjection('EPSG:4326');
 
   /**
    * @private
diff --git a/src/ol/format/KML.js b/src/ol/format/KML.js
index edfdd1dbf3..c2a70183f0 100644
--- a/src/ol/format/KML.js
+++ b/src/ol/format/KML.js
@@ -272,7 +272,7 @@ const KML = function(opt_options) {
   /**
    * @inheritDoc
    */
-  this.defaultDataProjection = getProjection('EPSG:4326');
+  this.dataProjection = getProjection('EPSG:4326');
 
   /**
    * @private
diff --git a/src/ol/format/MVT.js b/src/ol/format/MVT.js
index 355102a6c6..057c0fb7bc 100644
--- a/src/ol/format/MVT.js
+++ b/src/ol/format/MVT.js
@@ -56,7 +56,7 @@ const MVT = function(opt_options) {
   /**
    * @type {module:ol/proj/Projection}
    */
-  this.defaultDataProjection = new Projection({
+  this.dataProjection = new Projection({
     code: '',
     units: Units.TILE_PIXELS
   });
@@ -411,7 +411,7 @@ MVT.prototype.readFeatures = function(source, opt_options) {
  * @api
  */
 MVT.prototype.readProjection = function(source) {
-  return this.defaultDataProjection;
+  return this.dataProjection;
 };
 
 
diff --git a/src/ol/format/OSMXML.js b/src/ol/format/OSMXML.js
index c0b8ad611e..867abfed0c 100644
--- a/src/ol/format/OSMXML.js
+++ b/src/ol/format/OSMXML.js
@@ -30,7 +30,7 @@ const OSMXML = function() {
   /**
    * @inheritDoc
    */
-  this.defaultDataProjection = getProjection('EPSG:4326');
+  this.dataProjection = getProjection('EPSG:4326');
 };
 
 inherits(OSMXML, XMLFeature);
diff --git a/src/ol/format/Polyline.js b/src/ol/format/Polyline.js
index d45b46cd11..4cf8884b9d 100644
--- a/src/ol/format/Polyline.js
+++ b/src/ol/format/Polyline.js
@@ -41,7 +41,7 @@ const Polyline = function(opt_options) {
   /**
    * @inheritDoc
    */
-  this.defaultDataProjection = getProjection('EPSG:4326');
+  this.dataProjection = getProjection('EPSG:4326');
 
   /**
    * @private
diff --git a/src/ol/format/TextFeature.js b/src/ol/format/TextFeature.js
index cbe2914aa9..3b674d0d07 100644
--- a/src/ol/format/TextFeature.js
+++ b/src/ol/format/TextFeature.js
@@ -111,7 +111,7 @@ TextFeature.prototype.readProjection = function(source) {
  * @return {module:ol/proj/Projection} Projection.
  */
 TextFeature.prototype.readProjectionFromText = function(text) {
-  return this.defaultDataProjection;
+  return this.dataProjection;
 };
 
 
diff --git a/src/ol/format/TopoJSON.js b/src/ol/format/TopoJSON.js
index 9c5846cbc9..1fe14d9930 100644
--- a/src/ol/format/TopoJSON.js
+++ b/src/ol/format/TopoJSON.js
@@ -16,7 +16,7 @@ import {get as getProjection} from '../proj.js';
 
 /**
  * @typedef {Object} Options
- * @property {module:ol/proj~ProjectionLike} [defaultDataProjection='EPSG:4326'] Default data projection.
+ * @property {module:ol/proj~ProjectionLike} [dataProjection='EPSG:4326'] Default data projection.
  * @property {string} [layerName] Set the name of the TopoJSON topology
  * `objects`'s children as feature property with the specified name. This means
  * that when set to `'layer'`, a topology like
@@ -69,9 +69,9 @@ const TopoJSON = function(opt_options) {
   /**
    * @inheritDoc
    */
-  this.defaultDataProjection = getProjection(
-    options.defaultDataProjection ?
-      options.defaultDataProjection : 'EPSG:4326');
+  this.dataProjection = getProjection(
+    options.dataProjection ?
+      options.dataProjection : 'EPSG:4326');
 
 };
 
@@ -416,7 +416,7 @@ TopoJSON.prototype.readProjection;
  * @inheritDoc
  */
 TopoJSON.prototype.readProjectionFromObject = function(object) {
-  return this.defaultDataProjection;
+  return this.dataProjection;
 };
 
 
diff --git a/src/ol/format/XMLFeature.js b/src/ol/format/XMLFeature.js
index 9fbd783501..0267161fd4 100644
--- a/src/ol/format/XMLFeature.js
+++ b/src/ol/format/XMLFeature.js
@@ -190,7 +190,7 @@ XMLFeature.prototype.readProjection = function(source) {
  * @return {module:ol/proj/Projection} Projection.
  */
 XMLFeature.prototype.readProjectionFromDocument = function(doc) {
-  return this.defaultDataProjection;
+  return this.dataProjection;
 };
 
 
@@ -200,7 +200,7 @@ XMLFeature.prototype.readProjectionFromDocument = function(doc) {
  * @return {module:ol/proj/Projection} Projection.
  */
 XMLFeature.prototype.readProjectionFromNode = function(node) {
-  return this.defaultDataProjection;
+  return this.dataProjection;
 };
 
 
diff --git a/src/ol/source/Vector.js b/src/ol/source/Vector.js
index 23ed48266e..8e8f1550a9 100644
--- a/src/ol/source/Vector.js
+++ b/src/ol/source/Vector.js
@@ -122,7 +122,7 @@ inherits(VectorSourceEvent, Event);
  * during parsing. If your remote data source does not advertise its projection
  * properly, this transformation will be incorrect. For some formats, the
  * default projection (usually EPSG:4326) can be overridden by setting the
- * defaultDataProjection constructor option on the format.
+ * dataProjection constructor option on the format.
  * Note that if a source contains non-feature data, such as a GeoJSON geometry
  * or a KML NetworkLink, these will be ignored. Use a custom loader to load these.
  * @property {boolean} [useSpatialIndex=true]