diff --git a/src/library.cr b/src/library.cr
index 7d1f6ec..a0d8dcb 100644
--- a/src/library.cr
+++ b/src/library.cr
@@ -70,7 +70,70 @@ class Title
 	def get_entry(name)
 		@entries.find { |e| e.title == name }
 	end
+	def save_progress(username, entry, page)
+		info = TitleInfo.new @dir
+		if info.progress[username]?.nil?
+			info.progress[username] = {entry => page}
+			info.save @dir
+			return
+		end
+		info.progress[username][entry] = page
+		info.save @dir
+	end
+	def load_progress(username, entry : String)
+		info = TitleInfo.new @dir
+		if info.progress[username]?.nil?
+			return 0
+		end
+		if info.progress[username][entry]?.nil?
+			return 0
+		end
+		info.progress[username][entry]
+	end
+	def load_percetage(username, entry : String)
+		info = TitleInfo.new @dir
+		page = load_progress username, entry
+		entry_obj = get_entry entry
+		return 0 if entry_obj.nil?
+		page / entry_obj.pages
+	end
+	def load_percetage(username)
+		read_pages = 0
+		total_pages = 0
+		@entries.each do |e|
+			read_pages += load_progress username, e.title
+			total_pages += e.pages
+		end
+		read_pages / total_pages
+	end
+end
 
+class TitleInfo
+	# { user1: { entry1: 10, entry2: 0 } }
+	include JSON::Serializable
+
+	@[JSON::Field(key: "comment")]
+	property comment = "Generated by Mango. DO NOT EDIT!"
+
+	@[JSON::Field(key: "progress")]
+	property progress : Hash(String, Hash(String, Int32))
+
+	def initialize(title_dir)
+		info = nil
+
+		json_path = File.join title_dir, "info.json"
+		if File.exists? json_path
+			info = TitleInfo.from_json File.read json_path
+		else
+			info = TitleInfo.from_json "{\"progress\": {}}"
+		end
+
+		@progress = info.progress.clone
+	end
+	def save(title_dir)
+		json_path = File.join title_dir, "info.json"
+		File.write json_path, self.to_pretty_json
+	end
 end
 
 class Library
diff --git a/src/mango.cr b/src/mango.cr
index fb292cf..33a35e2 100644
--- a/src/mango.cr
+++ b/src/mango.cr
@@ -8,6 +8,8 @@ config = Config.load
 library = Library.new config.library_path
 storage = Storage.new config.db_path
 
+imgs_each_page = 5
+
 macro layout(name)
 	render "src/views/#{{{name}}}.ecr", "src/views/layout.ecr"
 end
@@ -32,17 +34,26 @@ def hash_to_query(hash)
 end
 
 get "/" do |env|
-	titles = library.titles
-	layout "index"
+	begin
+		titles = library.titles
+		username = (get_username env).not_nil!
+		percentage = titles.map &.load_percetage username
+		layout "index"
+	rescue
+		env.response.status_code = 500
+	end
 end
 
 get "/book/:title" do |env|
-	title = library.get_title env.params.url["title"]
-	if title.nil?
+	begin
+		title = (library.get_title env.params.url["title"]).not_nil!
+		username = (get_username env).not_nil!
+		percentage = title.entries.map { |e| title.load_percetage username,\
+								   e.title }
+		layout "title"
+	rescue
 		env.response.status_code = 404
-		next
 	end
-	layout "title"
 end
 
 get "/admin" do |env|
@@ -148,14 +159,23 @@ get "/reader/:title/:entry" do |env|
 	begin
 		title = (library.get_title env.params.url["title"]).not_nil!
 		entry = (title.get_entry env.params.url["entry"]).not_nil!
-		env.redirect "/reader/#{title.title}/#{entry.title}/0"
-	rescue
+
+		# load progress
+		username = get_username env
+		entry_page = title.load_progress username, entry.title
+		# we go above 1 * `imgs_each_page` pages. the infinite scroll library
+		# perloads a few pages in advance, and the user might not have actually
+		# read it
+		page = [(entry_page // imgs_each_page) - 1, 0].max
+
+		env.redirect "/reader/#{title.title}/#{entry.title}/#{page}"
+	rescue e
+		pp e
 		env.response.status_code = 404
 	end
 end
 
 get "/reader/:title/:entry/:page" do |env|
-	imgs_each_page = 5
 	# here each :page contains `imgs_each_page` images
 	begin
 		title = (library.get_title env.params.url["title"]).not_nil!
@@ -163,6 +183,10 @@ get "/reader/:title/:entry/:page" do |env|
 		page = env.params.url["page"].to_i
 		raise "" if page * imgs_each_page >= entry.pages
 
+		# save progress
+		username = (get_username env).not_nil!
+		title.save_progress username, entry.title, page * imgs_each_page
+
 		urls = ((page * imgs_each_page)...\
 			[entry.pages, (page + 1) * imgs_each_page].min) \
 			.map { |idx| "/api/page/#{title.title}/#{entry.title}/#{idx}" }
diff --git a/src/views/index.ecr b/src/views/index.ecr
index 6535a3d..dcb953a 100644
--- a/src/views/index.ecr
+++ b/src/views/index.ecr
@@ -1,7 +1,7 @@
 <h2 class=uk-title>Library</h2>
 <p class="uk-text-meta"><%= titles.size %> titles found</p>
 <div class="uk-child-width-1-4@m" uk-grid>
-  <%- titles.each do |t| -%>
+  <%- titles.each_with_index do |t, i| -%>
     <div>
       <a class="acard" href="/book/<%= t.title %>">
         <div class="uk-card uk-card-default">
@@ -9,7 +9,7 @@
               <img src="<%= t.entries[0].cover_url %>" alt="">
             </div>
             <div class="uk-card-body">
-              <div class="uk-card-badge uk-label">Badge</div>
+              <div class="uk-card-badge uk-label"><%= (percentage[i] * 100).round(1) %>%</div>
               <h3 class="uk-card-title"><%= t.title %></h3>
               <p><%= t.entries.size %> entries</p>
             </div>
diff --git a/src/views/title.ecr b/src/views/title.ecr
index fc7d77e..7abf7f9 100644
--- a/src/views/title.ecr
+++ b/src/views/title.ecr
@@ -1,7 +1,7 @@
 <h2 class=uk-title><%= title.title %></h2>
 <p class="uk-text-meta"><%= title.entries.size %> entries found</p>
 <div class="uk-child-width-1-4@m" uk-grid>
-  <%- title.entries.each do |e| -%>
+  <%- title.entries.each_with_index do |e, i| -%>
     <div>
       <a class="acard" href="/reader/<%= title.title %>/<%= e.title %>">
         <div class="uk-card uk-card-default">
@@ -9,7 +9,7 @@
               <img src="<%= e.cover_url %>" alt="">
             </div>
             <div class="uk-card-body">
-              <div class="uk-card-badge uk-label">Badge</div>
+              <div class="uk-card-badge uk-label"><%= (percentage[i] * 100).round(1) %>%</div>
               <h3 class="uk-card-title"><%= e.title %></h3>
             </div>
         </div>