diff --git a/src/ol/proj.js b/src/ol/proj.js
index 1a03ae6741..9dc6fb180f 100644
--- a/src/ol/proj.js
+++ b/src/ol/proj.js
@@ -4,7 +4,7 @@
 import {getDistance} from './sphere.js';
 import {applyTransform} from './extent.js';
 import {modulo} from './math.js';
-import EPSG3857 from './proj/EPSG3857.js';
+import {toEPSG4326, fromEPSG4326, PROJECTIONS as EPSG3857_PROJECTIONS} from './proj/epsg3857.js';
 import EPSG4326 from './proj/EPSG4326.js';
 import Projection from './proj/Projection.js';
 import Units from './proj/Units.js';
@@ -438,15 +438,15 @@ export function transformWithProjections(point, sourceProjection, destinationPro
 export function addCommon() {
   // Add transformations that don't alter coordinates to convert within set of
   // projections with equal meaning.
-  addEquivalentProjections(EPSG3857.PROJECTIONS);
+  addEquivalentProjections(EPSG3857_PROJECTIONS);
   addEquivalentProjections(EPSG4326.PROJECTIONS);
   // Add transformations to convert EPSG:4326 like coordinates to EPSG:3857 like
   // coordinates and back.
   addEquivalentTransforms(
     EPSG4326.PROJECTIONS,
-    EPSG3857.PROJECTIONS,
-    EPSG3857.fromEPSG4326,
-    EPSG3857.toEPSG4326);
+    EPSG3857_PROJECTIONS,
+    fromEPSG4326,
+    toEPSG4326);
 }
 
 addCommon();
diff --git a/src/ol/proj/EPSG3857.js b/src/ol/proj/epsg3857.js
similarity index 61%
rename from src/ol/proj/EPSG3857.js
rename to src/ol/proj/epsg3857.js
index a209fa210a..b4d939752d 100644
--- a/src/ol/proj/EPSG3857.js
+++ b/src/ol/proj/epsg3857.js
@@ -1,11 +1,43 @@
 /**
- * @module ol/proj/EPSG3857
+ * @module ol/proj/epsg3857
  */
 import {inherits} from '../index.js';
 import {cosh} from '../math.js';
 import Projection from '../proj/Projection.js';
 import Units from '../proj/Units.js';
-const _ol_proj_EPSG3857_ = {};
+
+
+/**
+ * Radius of WGS84 sphere
+ *
+ * @const
+ * @type {number}
+ */
+export const RADIUS = 6378137;
+
+
+/**
+ * @const
+ * @type {number}
+ */
+export const HALF_SIZE = Math.PI * RADIUS;
+
+
+/**
+ * @const
+ * @type {ol.Extent}
+ */
+export const EXTENT = [
+  -HALF_SIZE, -HALF_SIZE,
+  HALF_SIZE, HALF_SIZE
+];
+
+
+/**
+ * @const
+ * @type {ol.Extent}
+ */
+export const WORLD_EXTENT = [-180, -85, 180, 85];
 
 
 /**
@@ -15,54 +47,20 @@ const _ol_proj_EPSG3857_ = {};
  * @constructor
  * @extends {ol.proj.Projection}
  * @param {string} code Code.
- * @private
  */
-_ol_proj_EPSG3857_.Projection_ = function(code) {
+function EPSG3857Projection(code) {
   Projection.call(this, {
     code: code,
     units: Units.METERS,
-    extent: _ol_proj_EPSG3857_.EXTENT,
+    extent: EXTENT,
     global: true,
-    worldExtent: _ol_proj_EPSG3857_.WORLD_EXTENT,
+    worldExtent: WORLD_EXTENT,
     getPointResolution: function(resolution, point) {
-      return resolution / cosh(point[1] / _ol_proj_EPSG3857_.RADIUS);
+      return resolution / cosh(point[1] / RADIUS);
     }
   });
-};
-inherits(_ol_proj_EPSG3857_.Projection_, Projection);
-
-
-/**
- * Radius of WGS84 sphere
- *
- * @const
- * @type {number}
- */
-_ol_proj_EPSG3857_.RADIUS = 6378137;
-
-
-/**
- * @const
- * @type {number}
- */
-_ol_proj_EPSG3857_.HALF_SIZE = Math.PI * _ol_proj_EPSG3857_.RADIUS;
-
-
-/**
- * @const
- * @type {ol.Extent}
- */
-_ol_proj_EPSG3857_.EXTENT = [
-  -_ol_proj_EPSG3857_.HALF_SIZE, -_ol_proj_EPSG3857_.HALF_SIZE,
-  _ol_proj_EPSG3857_.HALF_SIZE, _ol_proj_EPSG3857_.HALF_SIZE
-];
-
-
-/**
- * @const
- * @type {ol.Extent}
- */
-_ol_proj_EPSG3857_.WORLD_EXTENT = [-180, -85, 180, 85];
+}
+inherits(EPSG3857Projection, Projection);
 
 
 /**
@@ -71,14 +69,14 @@ _ol_proj_EPSG3857_.WORLD_EXTENT = [-180, -85, 180, 85];
  * @const
  * @type {Array.<ol.proj.Projection>}
  */
-_ol_proj_EPSG3857_.PROJECTIONS = [
-  new _ol_proj_EPSG3857_.Projection_('EPSG:3857'),
-  new _ol_proj_EPSG3857_.Projection_('EPSG:102100'),
-  new _ol_proj_EPSG3857_.Projection_('EPSG:102113'),
-  new _ol_proj_EPSG3857_.Projection_('EPSG:900913'),
-  new _ol_proj_EPSG3857_.Projection_('urn:ogc:def:crs:EPSG:6.18:3:3857'),
-  new _ol_proj_EPSG3857_.Projection_('urn:ogc:def:crs:EPSG::3857'),
-  new _ol_proj_EPSG3857_.Projection_('http://www.opengis.net/gml/srs/epsg.xml#3857')
+export const PROJECTIONS = [
+  new EPSG3857Projection('EPSG:3857'),
+  new EPSG3857Projection('EPSG:102100'),
+  new EPSG3857Projection('EPSG:102113'),
+  new EPSG3857Projection('EPSG:900913'),
+  new EPSG3857Projection('urn:ogc:def:crs:EPSG:6.18:3:3857'),
+  new EPSG3857Projection('urn:ogc:def:crs:EPSG::3857'),
+  new EPSG3857Projection('http://www.opengis.net/gml/srs/epsg.xml#3857')
 ];
 
 
@@ -90,7 +88,7 @@ _ol_proj_EPSG3857_.PROJECTIONS = [
  * @param {number=} opt_dimension Dimension (default is `2`).
  * @return {Array.<number>} Output array of coordinate values.
  */
-_ol_proj_EPSG3857_.fromEPSG4326 = function(input, opt_output, opt_dimension) {
+export function fromEPSG4326(input, opt_output, opt_dimension) {
   const length = input.length;
   const dimension = opt_dimension > 1 ? opt_dimension : 2;
   let output = opt_output;
@@ -102,10 +100,10 @@ _ol_proj_EPSG3857_.fromEPSG4326 = function(input, opt_output, opt_dimension) {
       output = new Array(length);
     }
   }
-  const halfSize = _ol_proj_EPSG3857_.HALF_SIZE;
+  const halfSize = HALF_SIZE;
   for (let i = 0; i < length; i += dimension) {
     output[i] = halfSize * input[i] / 180;
-    let y = _ol_proj_EPSG3857_.RADIUS *
+    let y = RADIUS *
         Math.log(Math.tan(Math.PI * (input[i + 1] + 90) / 360));
     if (y > halfSize) {
       y = halfSize;
@@ -115,7 +113,7 @@ _ol_proj_EPSG3857_.fromEPSG4326 = function(input, opt_output, opt_dimension) {
     output[i + 1] = y;
   }
   return output;
-};
+}
 
 
 /**
@@ -126,7 +124,7 @@ _ol_proj_EPSG3857_.fromEPSG4326 = function(input, opt_output, opt_dimension) {
  * @param {number=} opt_dimension Dimension (default is `2`).
  * @return {Array.<number>} Output array of coordinate values.
  */
-_ol_proj_EPSG3857_.toEPSG4326 = function(input, opt_output, opt_dimension) {
+export function toEPSG4326(input, opt_output, opt_dimension) {
   const length = input.length;
   const dimension = opt_dimension > 1 ? opt_dimension : 2;
   let output = opt_output;
@@ -139,10 +137,9 @@ _ol_proj_EPSG3857_.toEPSG4326 = function(input, opt_output, opt_dimension) {
     }
   }
   for (let i = 0; i < length; i += dimension) {
-    output[i] = 180 * input[i] / _ol_proj_EPSG3857_.HALF_SIZE;
+    output[i] = 180 * input[i] / HALF_SIZE;
     output[i + 1] = 360 * Math.atan(
-      Math.exp(input[i + 1] / _ol_proj_EPSG3857_.RADIUS)) / Math.PI - 90;
+      Math.exp(input[i + 1] / RADIUS)) / Math.PI - 90;
   }
   return output;
-};
-export default _ol_proj_EPSG3857_;
+}
diff --git a/test/rendering/ol/reproj/image.test.js b/test/rendering/ol/reproj/image.test.js
index da5fef5100..1fd31adfb2 100644
--- a/test/rendering/ol/reproj/image.test.js
+++ b/test/rendering/ol/reproj/image.test.js
@@ -1,6 +1,6 @@
 import {listen} from '../../../../src/ol/events.js';
 import {get as getProjection} from '../../../../src/ol/proj.js';
-import _ol_proj_EPSG3857_ from '../../../../src/ol/proj/EPSG3857.js';
+import {HALF_SIZE} from '../../../../src/ol/proj/epsg3857.js';
 import ReprojImage from '../../../../src/ol/reproj/Image.js';
 import Static from '../../../../src/ol/source/ImageStatic.js';
 import _ol_tilegrid_ from '../../../../src/ol/tilegrid.js';
@@ -45,7 +45,7 @@ describe('ol.rendering.reproj.Image', function() {
     it('works for identity reprojection', function(done) {
       testSingleImage(source, 'EPSG:3857',
         _ol_tilegrid_.createXYZ().getTileCoordExtent([5, 5, -13]),
-        2 * _ol_proj_EPSG3857_.HALF_SIZE / (256 * (1 << 5)), 1,
+        2 * HALF_SIZE / (256 * (1 << 5)), 1,
         'rendering/ol/data/tiles/osm/5/5/12.png', done);
     });
 
diff --git a/test/spec/ol/proj.test.js b/test/spec/ol/proj.test.js
index 0c029d69cc..b7d9a5e02c 100644
--- a/test/spec/ol/proj.test.js
+++ b/test/spec/ol/proj.test.js
@@ -12,7 +12,7 @@ import {
   getTransformFromProjections
 } from '../../../src/ol/proj.js';
 import {register} from '../../../src/ol/proj/proj4.js';
-import _ol_proj_EPSG3857_ from '../../../src/ol/proj/EPSG3857.js';
+import {HALF_SIZE} from '../../../src/ol/proj/epsg3857.js';
 import _ol_proj_EPSG4326_ from '../../../src/ol/proj/EPSG4326.js';
 import Projection from '../../../src/ol/proj/Projection.js';
 
@@ -32,10 +32,10 @@ describe('ol.proj', function() {
       from: [-12356463.478053365, 5700582.732404122],
       to: [-111, 45.5]
     }, {
-      from: [2 * _ol_proj_EPSG3857_.HALF_SIZE - 12356463.478053365, 5700582.732404122],
+      from: [2 * HALF_SIZE - 12356463.478053365, 5700582.732404122],
       to: [-111, 45.5]
     }, {
-      from: [-4 * _ol_proj_EPSG3857_.HALF_SIZE - 12356463.478053365, 5700582.732404122],
+      from: [-4 * HALF_SIZE - 12356463.478053365, 5700582.732404122],
       to: [-111, 45.5]
     }];
 
diff --git a/test/spec/ol/proj/epsg3857.test.js b/test/spec/ol/proj/epsg3857.test.js
index 9535fe4587..85125e5667 100644
--- a/test/spec/ol/proj/epsg3857.test.js
+++ b/test/spec/ol/proj/epsg3857.test.js
@@ -1,7 +1,7 @@
 import {getPointResolution, transform, get as getProjection, clearAllProjections, addCommon} from '../../../../src/ol/proj.js';
-import _ol_proj_EPSG3857_ from '../../../../src/ol/proj/EPSG3857.js';
+import {fromEPSG4326, HALF_SIZE} from '../../../../src/ol/proj/epsg3857.js';
 
-describe('ol.proj.EPSG3857', function() {
+describe('ol/proj/epsg3857', function() {
 
   afterEach(function() {
     clearAllProjections();
@@ -11,9 +11,6 @@ describe('ol.proj.EPSG3857', function() {
   describe('fromEPSG4326()', function() {
 
     it('transforms from geographic to Web Mercator', function() {
-      const forward = _ol_proj_EPSG3857_.fromEPSG4326;
-      const edge = _ol_proj_EPSG3857_.HALF_SIZE;
-
       const tolerance = 1e-5;
 
       const cases = [{
@@ -21,10 +18,10 @@ describe('ol.proj.EPSG3857', function() {
         m: [0, 0]
       }, {
         g: [-180, -90],
-        m: [-edge, -edge]
+        m: [-HALF_SIZE, -HALF_SIZE]
       }, {
         g: [180, 90],
-        m: [edge, edge]
+        m: [HALF_SIZE, HALF_SIZE]
       }, {
         g: [-111.0429, 45.6770],
         m: [-12361239.084208, 5728738.469095]
@@ -32,7 +29,7 @@ describe('ol.proj.EPSG3857', function() {
 
       for (let i = 0, ii = cases.length; i < ii; ++i) {
         const point = cases[i].g;
-        const transformed = forward(point);
+        const transformed = fromEPSG4326(point);
         expect(transformed[0]).to.roughlyEqual(cases[i].m[0], tolerance);
         expect(transformed[1]).to.roughlyEqual(cases[i].m[1], tolerance);
       }
diff --git a/test/spec/ol/source/tileimage.test.js b/test/spec/ol/source/tileimage.test.js
index 206ec5b6d8..9a2497702a 100644
--- a/test/spec/ol/source/tileimage.test.js
+++ b/test/spec/ol/source/tileimage.test.js
@@ -4,7 +4,7 @@ import {createFromTemplate} from '../../../../src/ol/tileurlfunction.js';
 import {listen} from '../../../../src/ol/events.js';
 import {addCommon, clearAllProjections, get as getProjection} from '../../../../src/ol/proj.js';
 import {register} from '../../../../src/ol/proj/proj4.js';
-import _ol_proj_EPSG3857_ from '../../../../src/ol/proj/EPSG3857.js';
+import {WORLD_EXTENT} from '../../../../src/ol/proj/epsg3857.js';
 import Projection from '../../../../src/ol/proj/Projection.js';
 import ReprojTile from '../../../../src/ol/reproj/Tile.js';
 import TileImage from '../../../../src/ol/source/TileImage.js';
@@ -161,7 +161,7 @@ describe('ol.source.TileImage', function() {
       const source = createSource();
       source.setTileGridForProjection(proj,
         _ol_tilegrid_.createXYZ({
-          extent: _ol_proj_EPSG3857_.WORLD_EXTENT,
+          extent: WORLD_EXTENT,
           tileSize: [2, 2]
         }));
       const tile = source.getTile(0, 0, -1, 1, proj);
diff --git a/test/spec/ol/tilegrid/tilegrid.test.js b/test/spec/ol/tilegrid/tilegrid.test.js
index 4469bc969c..11c2c1d16b 100644
--- a/test/spec/ol/tilegrid/tilegrid.test.js
+++ b/test/spec/ol/tilegrid/tilegrid.test.js
@@ -2,7 +2,7 @@ import {DEFAULT_MAX_ZOOM, DEFAULT_TILE_SIZE} from '../../../../src/ol/tilegrid/c
 import TileRange from '../../../../src/ol/TileRange.js';
 import * as _ol_extent_ from '../../../../src/ol/extent.js';
 import {get as getProjection, METERS_PER_UNIT} from '../../../../src/ol/proj.js';
-import _ol_proj_EPSG3857_ from '../../../../src/ol/proj/EPSG3857.js';
+import {HALF_SIZE} from '../../../../src/ol/proj/epsg3857.js';
 import Projection from '../../../../src/ol/proj/Projection.js';
 import _ol_tilegrid_ from '../../../../src/ol/tilegrid.js';
 import TileGrid from '../../../../src/ol/tilegrid/TileGrid.js';
@@ -348,7 +348,7 @@ describe('ol.tilegrid.TileGrid', function() {
       const projection = getProjection('EPSG:3857');
       const grid = _ol_tilegrid_.createForProjection(projection);
       const origin = grid.getOrigin();
-      const half = _ol_proj_EPSG3857_.HALF_SIZE;
+      const half = HALF_SIZE;
       expect(origin).to.eql([-half, half]);
     });
 
@@ -357,7 +357,7 @@ describe('ol.tilegrid.TileGrid', function() {
       const grid = _ol_tilegrid_.createForProjection(
         projection, undefined, undefined, 'bottom-left');
       const origin = grid.getOrigin();
-      const half = _ol_proj_EPSG3857_.HALF_SIZE;
+      const half = HALF_SIZE;
       expect(origin).to.eql([-half, -half]);
     });
 
@@ -366,7 +366,7 @@ describe('ol.tilegrid.TileGrid', function() {
       const grid = _ol_tilegrid_.createForProjection(
         projection, undefined, undefined, 'bottom-right');
       const origin = grid.getOrigin();
-      const half = _ol_proj_EPSG3857_.HALF_SIZE;
+      const half = HALF_SIZE;
       expect(origin).to.eql([half, -half]);
     });
 
@@ -375,7 +375,7 @@ describe('ol.tilegrid.TileGrid', function() {
       const grid = _ol_tilegrid_.createForProjection(
         projection, undefined, undefined, 'top-left');
       const origin = grid.getOrigin();
-      const half = _ol_proj_EPSG3857_.HALF_SIZE;
+      const half = HALF_SIZE;
       expect(origin).to.eql([-half, half]);
     });
 
@@ -384,7 +384,7 @@ describe('ol.tilegrid.TileGrid', function() {
       const grid = _ol_tilegrid_.createForProjection(
         projection, undefined, undefined, 'top-right');
       const origin = grid.getOrigin();
-      const half = _ol_proj_EPSG3857_.HALF_SIZE;
+      const half = HALF_SIZE;
       expect(origin).to.eql([half, half]);
     });