diff --git a/data.json b/data.json
index c84a26c..15b2765 100644
--- a/data.json
+++ b/data.json
@@ -14,6 +14,15 @@
     "username_claimed": "red",
     "username_unclaimed": "noonewouldeverusethis7"
   },
+  "500px": {
+    "errorMsg": "No message available",
+    "errorType": "message",
+    "url": "https://500px.com/p/{}",
+    "urlMain": "https://500px.com/",
+    "urlProbe": "https://api.500px.com/graphql?operationName=ProfileRendererQuery&variables=%7B%22username%22%3A%22{}%22%7D&extensions=%7B%22persistedQuery%22%3A%7B%22version%22%3A1%2C%22sha256Hash%22%3A%224d02ff5c13927a3ac73b3eef306490508bc765956940c31051468cf30402a503%22%7D%7D",
+    "username_claimed": "blue",
+    "username_unclaimed": "noonewouldeverusethis7"
+  },
   "7Cups": {
     "errorType": "status_code",
     "url": "https://www.7cups.com/@{}",
@@ -104,6 +113,14 @@
     "username_claimed": "blue",
     "username_unclaimed": "noonewouldeverusethis7"
   },
+  "Atom Discussions": {
+    "errorMsg": "Oops! That page doesn\u2019t exist or is private.",
+    "errorType": "message",
+    "url": "https://discuss.atom.io/u/{}/summary",
+    "urlMain": "https://discuss.atom.io",
+    "username_claimed": "blue",
+    "username_unclaimed": "noonewouldeverusethis"
+  },
   "Audiojungle": {
     "errorType": "status_code",
     "regexCheck": "^[a-zA-Z0-9_]+$",
@@ -798,10 +815,10 @@
     "username_unclaimed": "noonewouldeverusethis7"
   },
   "Instructables": {
-    "errorMsg": "404: We're sorry, things break sometimes",
-    "errorType": "message",
+    "errorType": "status_code",
     "url": "https://www.instructables.com/member/{}",
     "urlMain": "https://www.instructables.com/",
+    "urlProbe": "https://www.instructables.com/json-api/showAuthorExists?screenName={}",
     "username_claimed": "blue",
     "username_unclaimed": "noonewouldeverusethis7"
   },
@@ -1228,9 +1245,17 @@
     "username_claimed": "Blue",
     "username_unclaimed": "noonewouldeverusethis"
   },
-  "Quora": {
+  "Quizlet": {
+    "errorMsg": "Page Unavailable",
     "errorType": "message",
+    "url": "https://quizlet.com/{}",
+    "urlMain": "https://quizlet.com",
+    "username_claimed": "blue",
+    "username_unclaimed": "noonewouldeverusethis"
+  },
+  "Quora": {
     "errorMsg": "Page Not Found",
+    "errorType": "message",
     "url": "https://www.quora.com/profile/{}",
     "urlMain": "https://www.quora.com/",
     "username_claimed": "Matt-Riggsby",
@@ -2275,4 +2300,4 @@
     "username_claimed": "blue",
     "username_unclaimed": "noonewouldeverusethis7"
   }
-}
+}
\ No newline at end of file
diff --git a/sites.md b/sites.md
index 9d43c0a..a7a7d9c 100644
--- a/sites.md
+++ b/sites.md
@@ -1,6 +1,7 @@
-# 300 sites are supported!
+# 303 sites are supported!
  - [2Dimensions](https://2Dimensions.com/)
  - [3dnews](http://forum.3dnews.ru/)
+ - [500px](https://500px.com/)
  - [7Cups](https://www.7cups.com/)
  - [9GAG](https://www.9gag.com/)
  - [About.me](https://about.me/)
@@ -13,6 +14,7 @@
  - [Asciinema](https://asciinema.org)
  - [Ask Fedora](https://ask.fedoraproject.org/)
  - [AskFM](https://ask.fm/)
+ - [Atom Discussions](https://discuss.atom.io)
  - [Audiojungle](https://audiojungle.net/)
  - [Avizo](https://www.avizo.cz/)
  - [BLIP.fm](https://blip.fm/)
@@ -160,6 +162,7 @@
  - [ProductHunt](https://www.producthunt.com/)
  - [PromoDJ](http://promodj.com/)
  - [PyPi](https://pypi.org)
+ - [Quizlet](https://quizlet.com)
  - [Quora](https://www.quora.com/)
  - [Raidforums](https://raidforums.com/)
  - [Rajce.net](https://www.rajce.idnes.cz/)