diff --git a/.gitignore b/.gitignore
index 20aa9132d7..55606b1502 100644
--- a/.gitignore
+++ b/.gitignore
@@ -36,3 +36,6 @@ screenshots/
 
 # Sobelow
 .sobelow
+
+# osx 
+.DS_Store
diff --git a/apps/block_scout_web/assets/js/app.js b/apps/block_scout_web/assets/js/app.js
index a01a3610b7..caa01d32d4 100644
--- a/apps/block_scout_web/assets/js/app.js
+++ b/apps/block_scout_web/assets/js/app.js
@@ -28,6 +28,7 @@ import './lib/market_history_chart'
 import './lib/reload_button'
 import './lib/tooltip'
 import './lib/smart_contract/read_only_functions'
+import './lib/smart_contract/wei_ether_converter'
 import './lib/pretty_json'
 import './lib/try_api'
 import './lib/token_balance_dropdown'
diff --git a/apps/block_scout_web/assets/js/lib/smart_contract/wei_ether_converter.js b/apps/block_scout_web/assets/js/lib/smart_contract/wei_ether_converter.js
new file mode 100644
index 0000000000..495cbce1a1
--- /dev/null
+++ b/apps/block_scout_web/assets/js/lib/smart_contract/wei_ether_converter.js
@@ -0,0 +1,27 @@
+import $ from 'jquery'
+import { BigNumber } from 'bignumber.js'
+
+const weiToEtherConverter = (element, event) => {
+  const weiUnit = '1000000000000000000'
+  const $element = $(element)
+  const $conversionTextWei = $element.find('[data-conversion-text-wei]')
+  const $conversionTextEth = $element.find('[data-conversion-text-eth]')
+  const $conversionUnit = $element.find('[data-conversion-unit]')
+  let unitVal = new BigNumber($conversionUnit.html())
+
+  if (event.target.checked) {
+    $conversionTextWei.css({display: 'none'})
+    $conversionTextEth.css({display: 'inline-block'})
+    unitVal = unitVal / new BigNumber(weiUnit)
+    $conversionUnit.html(String(unitVal > 0 ? unitVal : unitVal.toFixed(3)))
+  } else {
+    $conversionTextWei.css({display: 'inline-block'})
+    $conversionTextEth.css({display: 'none'})
+    unitVal = unitVal * new BigNumber(weiUnit)
+    $conversionUnit.html(unitVal)
+  }
+}
+
+$('[data-smart-contract-functions]').on('change', '[data-wei-ether-converter]', function (event) {
+  weiToEtherConverter(this, event)
+})
diff --git a/apps/block_scout_web/lib/block_scout_web/templates/smart_contract/_functions.html.eex b/apps/block_scout_web/lib/block_scout_web/templates/smart_contract/_functions.html.eex
index e03c1638ed..f3e71fd07d 100644
--- a/apps/block_scout_web/lib/block_scout_web/templates/smart_contract/_functions.html.eex
+++ b/apps/block_scout_web/lib/block_scout_web/templates/smart_contract/_functions.html.eex
@@ -41,7 +41,20 @@
                to: address_path(@conn, :show, output["value"])
              ) %>
           <% else %>
-            <%= output["value"] %>
+              <%= if output["type"] == "uint256" do %>
+                <div data-wei-ether-converter>
+                  <span data-conversion-unit>
+                    <%= output["value"] %>
+                  </span>
+                  <span class="py-2 px-2">
+                    <input class="wei-ether" type="checkbox" autocomplete="off"> 
+                    <span style="display: inline-block;" data-conversion-text-wei><%= gettext("WEI")%></span>
+                    <span style="display: none;" data-conversion-text-eth><%= gettext("ETH")%></span>
+                  <span>
+                </div>
+              <% else %>
+                <%= output["value"] %>
+              <% end %>
           <% end %>
         <% end %>
       </span>
diff --git a/apps/block_scout_web/priv/gettext/default.pot b/apps/block_scout_web/priv/gettext/default.pot
index 4bec2a2e0c..cf53c80999 100644
--- a/apps/block_scout_web/priv/gettext/default.pot
+++ b/apps/block_scout_web/priv/gettext/default.pot
@@ -688,6 +688,16 @@ msgstr ""
 msgid "Query"
 msgstr ""
 
+#, elixir-format
+#: lib/block_scout_web/templates/smart_contract/_functions.html.eex:51
+msgid "WEI"
+msgstr ""
+
+#, elixir-format
+#: lib/block_scout_web/templates/smart_contract/_functions.html.eex:52
+msgid "ETH"
+msgstr ""
+
 #, elixir-format
 #: lib/block_scout_web/templates/address_contract/index.html.eex:44
 #: lib/block_scout_web/templates/address_internal_transaction/index.html.eex:49
diff --git a/apps/block_scout_web/priv/gettext/en/LC_MESSAGES/default.po b/apps/block_scout_web/priv/gettext/en/LC_MESSAGES/default.po
index 9aa9c941da..e0219b52a7 100644
--- a/apps/block_scout_web/priv/gettext/en/LC_MESSAGES/default.po
+++ b/apps/block_scout_web/priv/gettext/en/LC_MESSAGES/default.po
@@ -700,6 +700,16 @@ msgstr ""
 msgid "Query"
 msgstr ""
 
+#, elixir-format
+#: lib/block_scout_web/templates/smart_contract/_functions.html.eex:51
+msgid "WEI"
+msgstr ""
+
+#, elixir-format
+#: lib/block_scout_web/templates/smart_contract/_functions.html.eex:52
+msgid "ETH"
+msgstr ""
+
 #, elixir-format
 #: lib/block_scout_web/templates/address_contract/index.html.eex:44
 #: lib/block_scout_web/templates/address_internal_transaction/index.html.eex:49
diff --git a/apps/explorer/package-lock.json b/apps/explorer/package-lock.json
index b9a98acabf..f3cce7e7a6 100644
--- a/apps/explorer/package-lock.json
+++ b/apps/explorer/package-lock.json
@@ -18,7 +18,7 @@
       "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.11.tgz",
       "integrity": "sha512-iCuPHDFgrHX7H2vEI/5xpz07zSHB00TpugqhmYtVmMO6518mCuRMoOYFldEBl0g187ufozdaHgWKcYFb61qGiA==",
       "requires": {
-        "balanced-match": "1.0.0",
+        "balanced-match": "^1.0.0",
         "concat-map": "0.0.1"
       }
     },
@@ -37,9 +37,9 @@
       "resolved": "https://registry.npmjs.org/cliui/-/cliui-3.2.0.tgz",
       "integrity": "sha1-EgYBU3qRbSmUD5NNo7SNWFo5IT0=",
       "requires": {
-        "string-width": "1.0.2",
-        "strip-ansi": "3.0.1",
-        "wrap-ansi": "2.1.0"
+        "string-width": "^1.0.1",
+        "strip-ansi": "^3.0.1",
+        "wrap-ansi": "^2.0.0"
       }
     },
     "code-point-at": {
@@ -62,7 +62,7 @@
       "resolved": "https://registry.npmjs.org/error-ex/-/error-ex-1.3.2.tgz",
       "integrity": "sha512-7dFHNmqeFSEt2ZBsCriorKnn3Z2pj+fd9kmI6QoWw4//DL+icEBfc0U7qJCisqrTsKTjw4fNFy2pW9OqStD84g==",
       "requires": {
-        "is-arrayish": "0.2.1"
+        "is-arrayish": "^0.2.1"
       }
     },
     "find-up": {
@@ -70,8 +70,8 @@
       "resolved": "https://registry.npmjs.org/find-up/-/find-up-1.1.2.tgz",
       "integrity": "sha1-ay6YIrGizgpgq2TWEOzK1TyyTQ8=",
       "requires": {
-        "path-exists": "2.1.0",
-        "pinkie-promise": "2.0.1"
+        "path-exists": "^2.0.0",
+        "pinkie-promise": "^2.0.0"
       }
     },
     "fs-extra": {
@@ -79,11 +79,11 @@
       "resolved": "https://registry.npmjs.org/fs-extra/-/fs-extra-0.30.0.tgz",
       "integrity": "sha1-8jP/zAjU2n1DLapEl3aYnbHfk/A=",
       "requires": {
-        "graceful-fs": "4.1.11",
-        "jsonfile": "2.4.0",
-        "klaw": "1.3.1",
-        "path-is-absolute": "1.0.1",
-        "rimraf": "2.6.2"
+        "graceful-fs": "^4.1.2",
+        "jsonfile": "^2.1.0",
+        "klaw": "^1.0.0",
+        "path-is-absolute": "^1.0.0",
+        "rimraf": "^2.2.8"
       }
     },
     "fs.realpath": {
@@ -101,12 +101,12 @@
       "resolved": "https://registry.npmjs.org/glob/-/glob-7.1.2.tgz",
       "integrity": "sha512-MJTUg1kjuLeQCJ+ccE4Vpa6kKVXkPYJ2mOCQyUuKLcLQsdrMCpBPUi8qVE6+YuaJkozeA9NusTAw3hLr8Xe5EQ==",
       "requires": {
-        "fs.realpath": "1.0.0",
-        "inflight": "1.0.6",
-        "inherits": "2.0.3",
-        "minimatch": "3.0.4",
-        "once": "1.4.0",
-        "path-is-absolute": "1.0.1"
+        "fs.realpath": "^1.0.0",
+        "inflight": "^1.0.4",
+        "inherits": "2",
+        "minimatch": "^3.0.4",
+        "once": "^1.3.0",
+        "path-is-absolute": "^1.0.0"
       }
     },
     "graceful-fs": {
@@ -124,8 +124,8 @@
       "resolved": "https://registry.npmjs.org/inflight/-/inflight-1.0.6.tgz",
       "integrity": "sha1-Sb1jMdfQLQwJvJEKEHW6gWW1bfk=",
       "requires": {
-        "once": "1.4.0",
-        "wrappy": "1.0.2"
+        "once": "^1.3.0",
+        "wrappy": "1"
       }
     },
     "inherits": {
@@ -148,7 +148,7 @@
       "resolved": "https://registry.npmjs.org/is-builtin-module/-/is-builtin-module-1.0.0.tgz",
       "integrity": "sha1-VAVy0096wxGfj3bDDLwbHgN6/74=",
       "requires": {
-        "builtin-modules": "1.1.1"
+        "builtin-modules": "^1.0.0"
       }
     },
     "is-fullwidth-code-point": {
@@ -156,7 +156,7 @@
       "resolved": "https://registry.npmjs.org/is-fullwidth-code-point/-/is-fullwidth-code-point-1.0.0.tgz",
       "integrity": "sha1-754xOG8DGn8NZDr4L95QxFfvAMs=",
       "requires": {
-        "number-is-nan": "1.0.1"
+        "number-is-nan": "^1.0.0"
       }
     },
     "is-utf8": {
@@ -169,7 +169,7 @@
       "resolved": "https://registry.npmjs.org/jsonfile/-/jsonfile-2.4.0.tgz",
       "integrity": "sha1-NzaitCi4e72gzIO1P6PWM6NcKug=",
       "requires": {
-        "graceful-fs": "4.1.11"
+        "graceful-fs": "^4.1.6"
       }
     },
     "klaw": {
@@ -177,7 +177,7 @@
       "resolved": "https://registry.npmjs.org/klaw/-/klaw-1.3.1.tgz",
       "integrity": "sha1-QIhDO0azsbolnXh4XY6W9zugJDk=",
       "requires": {
-        "graceful-fs": "4.1.11"
+        "graceful-fs": "^4.1.9"
       }
     },
     "lcid": {
@@ -185,7 +185,7 @@
       "resolved": "https://registry.npmjs.org/lcid/-/lcid-1.0.0.tgz",
       "integrity": "sha1-MIrMr6C8SDo4Z7S28rlQYlHRuDU=",
       "requires": {
-        "invert-kv": "1.0.0"
+        "invert-kv": "^1.0.0"
       }
     },
     "load-json-file": {
@@ -193,11 +193,11 @@
       "resolved": "https://registry.npmjs.org/load-json-file/-/load-json-file-1.1.0.tgz",
       "integrity": "sha1-lWkFcI1YtLq0wiYbBPWfMcmTdMA=",
       "requires": {
-        "graceful-fs": "4.1.11",
-        "parse-json": "2.2.0",
-        "pify": "2.3.0",
-        "pinkie-promise": "2.0.1",
-        "strip-bom": "2.0.0"
+        "graceful-fs": "^4.1.2",
+        "parse-json": "^2.2.0",
+        "pify": "^2.0.0",
+        "pinkie-promise": "^2.0.0",
+        "strip-bom": "^2.0.0"
       }
     },
     "lodash.assign": {
@@ -215,7 +215,7 @@
       "resolved": "https://registry.npmjs.org/minimatch/-/minimatch-3.0.4.tgz",
       "integrity": "sha512-yJHVQEhyqPLUTgt9B83PXu6W3rx4MvvHvSUvToogpwoGDOUQ+yDrR0HRot+yOCdCO7u4hX3pWft6kWBBcqh0UA==",
       "requires": {
-        "brace-expansion": "1.1.11"
+        "brace-expansion": "^1.1.7"
       }
     },
     "normalize-package-data": {
@@ -223,10 +223,10 @@
       "resolved": "https://registry.npmjs.org/normalize-package-data/-/normalize-package-data-2.4.0.tgz",
       "integrity": "sha512-9jjUFbTPfEy3R/ad/2oNbKtW9Hgovl5O1FvFWKkKblNXoN/Oou6+9+KKohPK13Yc3/TyunyWhJp6gvRNR/PPAw==",
       "requires": {
-        "hosted-git-info": "2.6.1",
-        "is-builtin-module": "1.0.0",
-        "semver": "5.5.0",
-        "validate-npm-package-license": "3.0.3"
+        "hosted-git-info": "^2.1.4",
+        "is-builtin-module": "^1.0.0",
+        "semver": "2 || 3 || 4 || 5",
+        "validate-npm-package-license": "^3.0.1"
       }
     },
     "number-is-nan": {
@@ -239,7 +239,7 @@
       "resolved": "https://registry.npmjs.org/once/-/once-1.4.0.tgz",
       "integrity": "sha1-WDsap3WWHUsROsF9nFC6753Xa9E=",
       "requires": {
-        "wrappy": "1.0.2"
+        "wrappy": "1"
       }
     },
     "os-locale": {
@@ -247,7 +247,7 @@
       "resolved": "https://registry.npmjs.org/os-locale/-/os-locale-1.4.0.tgz",
       "integrity": "sha1-IPnxeuKe00XoveWDsT0gCYA8FNk=",
       "requires": {
-        "lcid": "1.0.0"
+        "lcid": "^1.0.0"
       }
     },
     "parse-json": {
@@ -255,7 +255,7 @@
       "resolved": "https://registry.npmjs.org/parse-json/-/parse-json-2.2.0.tgz",
       "integrity": "sha1-9ID0BDTvgHQfhGkJn43qGPVaTck=",
       "requires": {
-        "error-ex": "1.3.2"
+        "error-ex": "^1.2.0"
       }
     },
     "path-exists": {
@@ -263,7 +263,7 @@
       "resolved": "https://registry.npmjs.org/path-exists/-/path-exists-2.1.0.tgz",
       "integrity": "sha1-D+tsZPD8UY2adU3V77YscCJ2H0s=",
       "requires": {
-        "pinkie-promise": "2.0.1"
+        "pinkie-promise": "^2.0.0"
       }
     },
     "path-is-absolute": {
@@ -276,9 +276,9 @@
       "resolved": "https://registry.npmjs.org/path-type/-/path-type-1.1.0.tgz",
       "integrity": "sha1-WcRPfuSR2nBNpBXaWkBwuk+P5EE=",
       "requires": {
-        "graceful-fs": "4.1.11",
-        "pify": "2.3.0",
-        "pinkie-promise": "2.0.1"
+        "graceful-fs": "^4.1.2",
+        "pify": "^2.0.0",
+        "pinkie-promise": "^2.0.0"
       }
     },
     "pify": {
@@ -296,7 +296,7 @@
       "resolved": "https://registry.npmjs.org/pinkie-promise/-/pinkie-promise-2.0.1.tgz",
       "integrity": "sha1-ITXW36ejWMBprJsXh3YogihFD/o=",
       "requires": {
-        "pinkie": "2.0.4"
+        "pinkie": "^2.0.0"
       }
     },
     "read-pkg": {
@@ -304,9 +304,9 @@
       "resolved": "https://registry.npmjs.org/read-pkg/-/read-pkg-1.1.0.tgz",
       "integrity": "sha1-9f+qXs0pyzHAR0vKfXVra7KePyg=",
       "requires": {
-        "load-json-file": "1.1.0",
-        "normalize-package-data": "2.4.0",
-        "path-type": "1.1.0"
+        "load-json-file": "^1.0.0",
+        "normalize-package-data": "^2.3.2",
+        "path-type": "^1.0.0"
       }
     },
     "read-pkg-up": {
@@ -314,8 +314,8 @@
       "resolved": "https://registry.npmjs.org/read-pkg-up/-/read-pkg-up-1.0.1.tgz",
       "integrity": "sha1-nWPBMnbAZZGNV/ACpX9AobZD+wI=",
       "requires": {
-        "find-up": "1.1.2",
-        "read-pkg": "1.1.0"
+        "find-up": "^1.0.0",
+        "read-pkg": "^1.0.0"
       }
     },
     "require-directory": {
@@ -338,7 +338,7 @@
       "resolved": "https://registry.npmjs.org/rimraf/-/rimraf-2.6.2.tgz",
       "integrity": "sha512-lreewLK/BlghmxtfH36YYVg1i8IAce4TI7oao75I1g245+6BctqTVQiBP3YUJ9C6DQOXJmkYR9X9fCLtCOJc5w==",
       "requires": {
-        "glob": "7.1.2"
+        "glob": "^7.0.5"
       }
     },
     "semver": {
@@ -356,11 +356,11 @@
       "resolved": "https://registry.npmjs.org/solc-js/-/solc-js-0.4.20.tgz",
       "integrity": "sha1-tjCVsPcatkx6fi+C7YUtCzUxTlg=",
       "requires": {
-        "fs-extra": "0.30.0",
-        "memorystream": "0.3.1",
-        "require-from-string": "1.2.1",
-        "semver": "5.5.0",
-        "yargs": "4.8.1"
+        "fs-extra": "^0.30.0",
+        "memorystream": "^0.3.1",
+        "require-from-string": "^1.1.0",
+        "semver": "^5.3.0",
+        "yargs": "^4.7.1"
       }
     },
     "spdx-correct": {
@@ -368,8 +368,8 @@
       "resolved": "https://registry.npmjs.org/spdx-correct/-/spdx-correct-3.0.0.tgz",
       "integrity": "sha512-N19o9z5cEyc8yQQPukRCZ9EUmb4HUpnrmaL/fxS2pBo2jbfcFRVuFZ/oFC+vZz0MNNk0h80iMn5/S6qGZOL5+g==",
       "requires": {
-        "spdx-expression-parse": "3.0.0",
-        "spdx-license-ids": "3.0.0"
+        "spdx-expression-parse": "^3.0.0",
+        "spdx-license-ids": "^3.0.0"
       }
     },
     "spdx-exceptions": {
@@ -382,8 +382,8 @@
       "resolved": "https://registry.npmjs.org/spdx-expression-parse/-/spdx-expression-parse-3.0.0.tgz",
       "integrity": "sha512-Yg6D3XpRD4kkOmTpdgbUiEJFKghJH03fiC1OPll5h/0sO6neh2jqRDVHOQ4o/LMea0tgCkbMgea5ip/e+MkWyg==",
       "requires": {
-        "spdx-exceptions": "2.1.0",
-        "spdx-license-ids": "3.0.0"
+        "spdx-exceptions": "^2.1.0",
+        "spdx-license-ids": "^3.0.0"
       }
     },
     "spdx-license-ids": {
@@ -396,9 +396,9 @@
       "resolved": "https://registry.npmjs.org/string-width/-/string-width-1.0.2.tgz",
       "integrity": "sha1-EYvfW4zcUaKn5w0hHgfisLmxB9M=",
       "requires": {
-        "code-point-at": "1.1.0",
-        "is-fullwidth-code-point": "1.0.0",
-        "strip-ansi": "3.0.1"
+        "code-point-at": "^1.0.0",
+        "is-fullwidth-code-point": "^1.0.0",
+        "strip-ansi": "^3.0.0"
       }
     },
     "strip-ansi": {
@@ -406,7 +406,7 @@
       "resolved": "https://registry.npmjs.org/strip-ansi/-/strip-ansi-3.0.1.tgz",
       "integrity": "sha1-ajhfuIU9lS1f8F0Oiq+UJ43GPc8=",
       "requires": {
-        "ansi-regex": "2.1.1"
+        "ansi-regex": "^2.0.0"
       }
     },
     "strip-bom": {
@@ -414,7 +414,7 @@
       "resolved": "https://registry.npmjs.org/strip-bom/-/strip-bom-2.0.0.tgz",
       "integrity": "sha1-YhmoVhZSBJHzV4i9vxRHqZx+aw4=",
       "requires": {
-        "is-utf8": "0.2.1"
+        "is-utf8": "^0.2.0"
       }
     },
     "validate-npm-package-license": {
@@ -422,8 +422,8 @@
       "resolved": "https://registry.npmjs.org/validate-npm-package-license/-/validate-npm-package-license-3.0.3.tgz",
       "integrity": "sha512-63ZOUnL4SIXj4L0NixR3L1lcjO38crAbgrTpl28t8jjrfuiOBL5Iygm+60qPs/KsZGzPNg6Smnc/oY16QTjF0g==",
       "requires": {
-        "spdx-correct": "3.0.0",
-        "spdx-expression-parse": "3.0.0"
+        "spdx-correct": "^3.0.0",
+        "spdx-expression-parse": "^3.0.0"
       }
     },
     "which-module": {
@@ -441,8 +441,8 @@
       "resolved": "https://registry.npmjs.org/wrap-ansi/-/wrap-ansi-2.1.0.tgz",
       "integrity": "sha1-2Pw9KE3QV5T+hJc8rs3Rz4JP3YU=",
       "requires": {
-        "string-width": "1.0.2",
-        "strip-ansi": "3.0.1"
+        "string-width": "^1.0.1",
+        "strip-ansi": "^3.0.1"
       }
     },
     "wrappy": {
@@ -460,20 +460,20 @@
       "resolved": "https://registry.npmjs.org/yargs/-/yargs-4.8.1.tgz",
       "integrity": "sha1-wMQpJMpKqmsObaFznfshZDn53cA=",
       "requires": {
-        "cliui": "3.2.0",
-        "decamelize": "1.2.0",
-        "get-caller-file": "1.0.2",
-        "lodash.assign": "4.2.0",
-        "os-locale": "1.4.0",
-        "read-pkg-up": "1.0.1",
-        "require-directory": "2.1.1",
-        "require-main-filename": "1.0.1",
-        "set-blocking": "2.0.0",
-        "string-width": "1.0.2",
-        "which-module": "1.0.0",
-        "window-size": "0.2.0",
-        "y18n": "3.2.1",
-        "yargs-parser": "2.4.1"
+        "cliui": "^3.2.0",
+        "decamelize": "^1.1.1",
+        "get-caller-file": "^1.0.1",
+        "lodash.assign": "^4.0.3",
+        "os-locale": "^1.4.0",
+        "read-pkg-up": "^1.0.1",
+        "require-directory": "^2.1.1",
+        "require-main-filename": "^1.0.1",
+        "set-blocking": "^2.0.0",
+        "string-width": "^1.0.1",
+        "which-module": "^1.0.0",
+        "window-size": "^0.2.0",
+        "y18n": "^3.2.1",
+        "yargs-parser": "^2.4.1"
       }
     },
     "yargs-parser": {
@@ -481,8 +481,8 @@
       "resolved": "https://registry.npmjs.org/yargs-parser/-/yargs-parser-2.4.1.tgz",
       "integrity": "sha1-hVaN488VD/SfpRgl8DqMiA3cxcQ=",
       "requires": {
-        "camelcase": "3.0.0",
-        "lodash.assign": "4.2.0"
+        "camelcase": "^3.0.0",
+        "lodash.assign": "^4.0.6"
       }
     }
   }