diff --git a/app/controllers/post_regenerations_controller.rb b/app/controllers/post_regenerations_controller.rb
new file mode 100644
index 000000000..f7466e0cc
--- /dev/null
+++ b/app/controllers/post_regenerations_controller.rb
@@ -0,0 +1,18 @@
+class PostRegenerationsController < ApplicationController
+  respond_to :html, :xml, :json, :js
+
+  def create
+    @post_regeneration = authorize PostRegeneration.new(creator: CurrentUser.user, **permitted_attributes(PostRegeneration))
+    @post_regeneration.execute_category_action!
+    @post_regeneration.save
+
+    respond_with(@post_regeneration, location: @post_regeneration.post)
+  end
+
+  def index
+    @post_regenerations = authorize PostRegeneration.paginated_search(params)
+    @post_regenerations = @post_regenerations.includes(:creator, :post) if request.format.html?
+
+    respond_with(@post_regenerations)
+  end
+end
diff --git a/app/logical/upload_service/utils.rb b/app/logical/upload_service/utils.rb
index 1ec214222..ec781d5dc 100644
--- a/app/logical/upload_service/utils.rb
+++ b/app/logical/upload_service/utils.rb
@@ -32,6 +32,22 @@ class UploadService
       [preview_file, crop_file, sample_file]
     end
 
+    def process_resizes(upload, file, original_post_id, media_file: nil)
+      media_file ||= upload.media_file
+      preview_file, crop_file, sample_file = Utils.generate_resizes(media_file)
+
+      begin
+        Utils.distribute_files(file, upload, :original, original_post_id: original_post_id) if file.present?
+        Utils.distribute_files(sample_file, upload, :large, original_post_id: original_post_id) if sample_file.present?
+        Utils.distribute_files(preview_file, upload, :preview, original_post_id: original_post_id) if preview_file.present?
+        Utils.distribute_files(crop_file, upload, :crop, original_post_id: original_post_id) if crop_file.present?
+      ensure
+        preview_file.try(:close!)
+        crop_file.try(:close!)
+        sample_file.try(:close!)
+      end
+    end
+
     def process_file(upload, file, original_post_id: nil)
       upload.file = file
       media_file = upload.media_file
@@ -45,18 +61,7 @@ class UploadService
       upload.validate!(:file)
       upload.tag_string = "#{upload.tag_string} #{Utils.automatic_tags(media_file)}"
 
-      preview_file, crop_file, sample_file = Utils.generate_resizes(media_file)
-
-      begin
-        Utils.distribute_files(file, upload, :original, original_post_id: original_post_id)
-        Utils.distribute_files(sample_file, upload, :large, original_post_id: original_post_id) if sample_file.present?
-        Utils.distribute_files(preview_file, upload, :preview, original_post_id: original_post_id) if preview_file.present?
-        Utils.distribute_files(crop_file, upload, :crop, original_post_id: original_post_id) if crop_file.present?
-      ensure
-        preview_file.try(:close!)
-        crop_file.try(:close!)
-        sample_file.try(:close!)
-      end
+      process_resizes(upload, file, original_post_id)
     end
 
     def automatic_tags(media_file)
diff --git a/app/models/post_regeneration.rb b/app/models/post_regeneration.rb
new file mode 100644
index 000000000..729f8740c
--- /dev/null
+++ b/app/models/post_regeneration.rb
@@ -0,0 +1,31 @@
+class PostRegeneration < ApplicationRecord
+  belongs_to :creator, :class_name => "User"
+  belongs_to :post
+
+  validates :category, inclusion: %w[iqdb resizes]
+
+  module SearchMethods
+    def search(params)
+      q = search_attributes(params, :id, :created_at, :updated_at, :category, :creator, :post)
+      q.apply_default_order(params)
+    end
+  end
+
+  extend SearchMethods
+
+  def execute_category_action!
+    if category == "iqdb"
+      post.update_iqdb_async
+    elsif category == "resizes"
+      media_file = MediaFile.open(post.file, frame_data: post.pixiv_ugoira_frame_data)
+      UploadService::Utils.process_resizes(post, nil, post.id, media_file: media_file)
+    else
+      # should never happen
+      raise Error, "Unknown category: #{category}"
+    end
+  end
+
+  def self.searchable_includes
+    [:creator, :post]
+  end
+end
diff --git a/app/policies/post_regeneration_policy.rb b/app/policies/post_regeneration_policy.rb
new file mode 100644
index 000000000..25cc57956
--- /dev/null
+++ b/app/policies/post_regeneration_policy.rb
@@ -0,0 +1,9 @@
+class PostRegenerationPolicy < ApplicationPolicy
+  def create?
+    user.is_moderator?
+  end
+
+  def permitted_attributes_for_create
+    [:post_id, :category]
+  end
+end
diff --git a/app/views/post_regenerations/create.js.erb b/app/views/post_regenerations/create.js.erb
new file mode 100644
index 000000000..d45a54f1e
--- /dev/null
+++ b/app/views/post_regenerations/create.js.erb
@@ -0,0 +1,5 @@
+<% if @post_regeneration.errors.any? %>
+  Danbooru.error("<%= j @post_regeneration.errors.full_messages.join(',') %>");
+<% else %>
+  Danbooru.notice("Post regenerated");
+<% end %>
diff --git a/app/views/post_regenerations/index.html.erb b/app/views/post_regenerations/index.html.erb
new file mode 100644
index 000000000..cea7ac3a1
--- /dev/null
+++ b/app/views/post_regenerations/index.html.erb
@@ -0,0 +1,17 @@
+<div id="c-post-regenerations">
+  <div id="a-index">
+    <h1>Post regenerations</h1>
+    <%= table_for @post_regenerations, width: "100%" do |t| %>
+      <% t.column "Post", width: "1%" do |regeneration| %>
+        <%= PostPresenter.preview(regeneration.post, show_deleted: true) %>
+      <% end %>
+      <% t.column :category %>
+      <% t.column "Creator", width: "10%" do |regeneration| %>
+        <%= compact_time regeneration.created_at %>
+        <br> by <%= link_to_user regeneration.creator %>
+      <% end %>
+    <% end %>
+
+    <%= numbered_paginator(@post_regenerations) %>
+  </div>
+</div>
diff --git a/app/views/posts/partials/show/_options.html.erb b/app/views/posts/partials/show/_options.html.erb
index 7190bdf4c..2b336a854 100644
--- a/app/views/posts/partials/show/_options.html.erb
+++ b/app/views/posts/partials/show/_options.html.erb
@@ -86,4 +86,9 @@
         <li id="post-option-replace-image"><%= link_to "Replace image", new_post_replacement_path(post_id: post.id), remote: true %></li>
       <% end %>
     <% end %>
+
+    <% if policy(PostRegeneration).create? %>
+      <li id="post-option-regenerate-iqdb"><%= link_to "Regenerate IQDB", post_regenerations_path(post_regeneration: {post_id: post.id, category: "iqdb"}), remote: true, method: :post %></li>
+      <li id="post-option-regenerate-preview"><%= link_to "Regenerate image sizes", post_regenerations_path(post_regeneration: {post_id: post.id, category: "resizes"}), remote: true, method: :post %></li>
+    <% end %>
 </ul>
diff --git a/app/views/posts/show.html.erb b/app/views/posts/show.html.erb
index a2f202f27..6f5152225 100644
--- a/app/views/posts/show.html.erb
+++ b/app/views/posts/show.html.erb
@@ -33,6 +33,7 @@
       <li id="post-history-moderation"><%= link_to "Moderation", post_events_path(@post.id) %></li>
       <li id="post-history-commentary"><%= link_to "Commentary", artist_commentary_versions_path(search: { post_id: @post.id }) %></li>
       <li id="post-history-replacements"><%= link_to "Replacements", post_replacements_path(search: {post_id: @post.id }) %></li>
+      <li id="post-history-regenerations"><%= link_to "Regenerations", post_regenerations_path(search: {post_id: @post.id }) %></li>
     </ul>
   </section>
 <% end %>
diff --git a/config/routes.rb b/config/routes.rb
index 13e8a809c..5fa7b3238 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -178,6 +178,7 @@ Rails.application.routes.draw do
       get :search
     end
   end
+  resources :post_regenerations, :only => [:index, :create]
   resources :post_replacements, :only => [:index, :new, :create, :update]
   resources :post_votes, only: [:index]
 
diff --git a/db/migrate/20201121180345_create_post_regenerations.rb b/db/migrate/20201121180345_create_post_regenerations.rb
new file mode 100644
index 000000000..ec88f7bbe
--- /dev/null
+++ b/db/migrate/20201121180345_create_post_regenerations.rb
@@ -0,0 +1,13 @@
+class CreatePostRegenerations < ActiveRecord::Migration[6.0]
+  def change
+    create_table :post_regenerations do |t|
+      t.timestamps
+      t.integer :creator_id, null: false
+      t.integer :post_id, null: false
+      t.string :category, null: false
+
+      t.index :creator_id
+      t.index :post_id
+    end
+  end
+end
diff --git a/db/structure.sql b/db/structure.sql
index f57281afa..3afb26718 100644
--- a/db/structure.sql
+++ b/db/structure.sql
@@ -2724,6 +2724,39 @@ CREATE SEQUENCE public.post_flags_id_seq
 ALTER SEQUENCE public.post_flags_id_seq OWNED BY public.post_flags.id;
 
 
+--
+-- Name: post_regenerations; Type: TABLE; Schema: public; Owner: -
+--
+
+CREATE TABLE public.post_regenerations (
+    id bigint NOT NULL,
+    created_at timestamp(6) without time zone NOT NULL,
+    updated_at timestamp(6) without time zone NOT NULL,
+    creator_id integer NOT NULL,
+    post_id integer NOT NULL,
+    category character varying NOT NULL
+);
+
+
+--
+-- Name: post_regenerations_id_seq; Type: SEQUENCE; Schema: public; Owner: -
+--
+
+CREATE SEQUENCE public.post_regenerations_id_seq
+    START WITH 1
+    INCREMENT BY 1
+    NO MINVALUE
+    NO MAXVALUE
+    CACHE 1;
+
+
+--
+-- Name: post_regenerations_id_seq; Type: SEQUENCE OWNED BY; Schema: public; Owner: -
+--
+
+ALTER SEQUENCE public.post_regenerations_id_seq OWNED BY public.post_regenerations.id;
+
+
 --
 -- Name: post_replacements; Type: TABLE; Schema: public; Owner: -
 --
@@ -4137,6 +4170,13 @@ ALTER TABLE ONLY public.post_disapprovals ALTER COLUMN id SET DEFAULT nextval('p
 ALTER TABLE ONLY public.post_flags ALTER COLUMN id SET DEFAULT nextval('public.post_flags_id_seq'::regclass);
 
 
+--
+-- Name: post_regenerations id; Type: DEFAULT; Schema: public; Owner: -
+--
+
+ALTER TABLE ONLY public.post_regenerations ALTER COLUMN id SET DEFAULT nextval('public.post_regenerations_id_seq'::regclass);
+
+
 --
 -- Name: post_replacements id; Type: DEFAULT; Schema: public; Owner: -
 --
@@ -4499,6 +4539,14 @@ ALTER TABLE ONLY public.post_flags
     ADD CONSTRAINT post_flags_pkey PRIMARY KEY (id);
 
 
+--
+-- Name: post_regenerations post_regenerations_pkey; Type: CONSTRAINT; Schema: public; Owner: -
+--
+
+ALTER TABLE ONLY public.post_regenerations
+    ADD CONSTRAINT post_regenerations_pkey PRIMARY KEY (id);
+
+
 --
 -- Name: post_replacements post_replacements_pkey; Type: CONSTRAINT; Schema: public; Owner: -
 --
@@ -6752,6 +6800,20 @@ CREATE INDEX index_post_flags_on_reason_tsvector ON public.post_flags USING gin
 CREATE INDEX index_post_flags_on_status ON public.post_flags USING btree (status);
 
 
+--
+-- Name: index_post_regenerations_on_creator_id; Type: INDEX; Schema: public; Owner: -
+--
+
+CREATE INDEX index_post_regenerations_on_creator_id ON public.post_regenerations USING btree (creator_id);
+
+
+--
+-- Name: index_post_regenerations_on_post_id; Type: INDEX; Schema: public; Owner: -
+--
+
+CREATE INDEX index_post_regenerations_on_post_id ON public.post_regenerations USING btree (post_id);
+
+
 --
 -- Name: index_post_replacements_on_creator_id; Type: INDEX; Schema: public; Owner: -
 --
@@ -7520,6 +7582,7 @@ INSERT INTO "schema_migrations" (version) VALUES
 ('20200520060951'),
 ('20200803022359'),
 ('20200816175151'),
+('20201121180345'),
 ('20201201211748'),
 ('20201213052805'),
 ('20201219201007'),
diff --git a/test/factories/post_regeneration.rb b/test/factories/post_regeneration.rb
new file mode 100644
index 000000000..00087ac02
--- /dev/null
+++ b/test/factories/post_regeneration.rb
@@ -0,0 +1,5 @@
+FactoryBot.define do
+  factory(:post_regeneration) do
+    post factory: :post, source: FFaker::Internet.http_url
+  end
+end
diff --git a/test/functional/post_regenerations_controller_test.rb b/test/functional/post_regenerations_controller_test.rb
new file mode 100644
index 000000000..119d5741a
--- /dev/null
+++ b/test/functional/post_regenerations_controller_test.rb
@@ -0,0 +1,49 @@
+require 'test_helper'
+
+class PostRegenerationsControllerTest < ActionDispatch::IntegrationTest
+  context "The post regenerations controller" do
+    setup do
+      @mod = create(:moderator_user, name: "yukari", created_at: 1.month.ago)
+      as(@mod) do
+        @post = create(:post, source: "https://google.com", tag_string: "touhou")
+        @post_regeneration = create(:post_regeneration, creator: @mod, category: "iqdb")
+      end
+    end
+
+    context "create action" do
+      should "render" do
+        assert_difference("PostRegeneration.count") do
+          post_auth post_regenerations_path, @mod, params: {format: :json, post_regeneration: {post_id: @post.id, category: "iqdb"}}
+          assert_response :success
+        end
+      end
+
+      should "not allow non-mods to regenerate posts" do
+        assert_difference("PostRegeneration.count", 0) do
+          post_auth post_regenerations_path, create(:user), params: {format: :json, post_regeneration: {post_id: @post.id, category: "iqdb"}}
+          assert_response 403
+        end
+      end
+    end
+
+    context "index action" do
+      setup do
+        @admin = create(:admin_user)
+        as(@admin) { @admin_regeneration = create(:post_regeneration, post: @post, creator: @admin, category: "resizes") }
+      end
+
+      should "render" do
+        get post_regenerations_path
+        assert_response :success
+      end
+
+      should respond_to_search({}).with { [@admin_regeneration, @post_regeneration] }
+      should respond_to_search(category: "iqdb").with { @post_regeneration }
+
+      context "using includes" do
+        should respond_to_search(post_tags_match: "touhou").with { @admin_regeneration }
+        should respond_to_search(creator: {level: User::Levels::ADMIN}).with { @admin_regeneration }
+      end
+    end
+  end
+end