diff --git a/src/codecs/resize/options.tsx b/src/codecs/resize/options.tsx
index c6e461a7..02e2023d 100644
--- a/src/codecs/resize/options.tsx
+++ b/src/codecs/resize/options.tsx
@@ -1,8 +1,11 @@
 import { h, Component } from 'preact';
 import linkState from 'linkstate';
-import { bind } from '../../lib/initial-util';
+import { bind, linkRef } from '../../lib/initial-util';
 import { inputFieldValueAsNumber } from '../../lib/util';
 import { ResizeOptions } from './processor-meta';
+import * as style from '../../components/options/style.scss';
+import Checkbox from '../../components/checkbox';
+import Expander from '../../components/expander';
 
 interface Props {
   isVector: Boolean;
@@ -32,7 +35,7 @@ export default class ResizerOptions extends Component<Props, State> {
       width: inputFieldValueAsNumber(width),
       height: inputFieldValueAsNumber(height),
       method: this.form!.resizeMethod.value,
-      fitMethod: this.form!.fitMethod.value,
+      fitMethod: this.form!.fitMethod ? this.form!.fitMethod.value : this.props.options.fitMethod,
     };
     this.props.onChange(options);
   }
@@ -65,10 +68,10 @@ export default class ResizerOptions extends Component<Props, State> {
     this.form!.width.value = Math.round(height * this.props.aspect);
   }
 
-  render({ options, aspect, isVector }: Props, { maintainAspect }: State) {
+  render({ options, isVector }: Props, { maintainAspect }: State) {
     return (
-      <form ref={el => this.form = el}>
-        <label>
+      <form ref={linkRef(this, 'form')} class={style.optionsSection}>
+        <label class={style.optionTextFirst}>
           Method:
           <select
             name="resizeMethod"
@@ -82,7 +85,7 @@ export default class ResizerOptions extends Component<Props, State> {
             <option value="browser-high">Browser high quality</option>
           </select>
         </label>
-        <label>
+        <label class={style.optionTextFirst}>
           Width:
           <input
             required
@@ -94,7 +97,7 @@ export default class ResizerOptions extends Component<Props, State> {
             onInput={this.onWidthInput}
           />
         </label>
-        <label>
+        <label class={style.optionTextFirst}>
           Height:
           <input
             required
@@ -105,26 +108,29 @@ export default class ResizerOptions extends Component<Props, State> {
             onChange={this.onChange}
           />
         </label>
-        <label>
-          <input
+        <label class={style.optionInputFirst}>
+          <Checkbox
             name="maintainAspect"
-            type="checkbox"
             checked={maintainAspect}
             onChange={linkState(this, 'maintainAspect')}
           />
           Maintain aspect ratio
         </label>
-        <label style={{ display: maintainAspect ? 'none' : '' }}>
-          Fit method:
-          <select
-            name="fitMethod"
-            value={options.fitMethod}
-            onChange={this.onChange}
-          >
-            <option value="stretch">Stretch</option>
-            <option value="cover">Cover</option>
-          </select>
-        </label>
+        <Expander>
+          {maintainAspect ? null :
+            <label class={style.optionTextFirst}>
+              Fit method:
+              <select
+                name="fitMethod"
+                value={options.fitMethod}
+                onChange={this.onChange}
+              >
+                <option value="stretch">Stretch</option>
+                <option value="cover">Cover</option>
+              </select>
+            </label>
+          }
+        </Expander>
       </form>
     );
   }
diff --git a/src/components/Options/index.tsx b/src/components/Options/index.tsx
index e82ccd00..45f3cf01 100644
--- a/src/components/Options/index.tsx
+++ b/src/components/Options/index.tsx
@@ -3,7 +3,7 @@ import { h, Component } from 'preact';
 import * as style from './style.scss';
 import { bind, Fileish } from '../../lib/initial-util';
 import { cleanSet, cleanMerge } from '../../lib/clean-modify';
-/*import OptiPNGEncoderOptions from '../../codecs/optipng/options';
+import OptiPNGEncoderOptions from '../../codecs/optipng/options';
 import MozJpegEncoderOptions from '../../codecs/mozjpeg/options';
 import BrowserJPEGEncoderOptions from '../../codecs/browser-jpeg/options';
 import WebPEncoderOptions from '../../codecs/webp/options';
@@ -23,24 +23,24 @@ import * as browserGIF from '../../codecs/browser-gif/encoder-meta';
 import * as browserTIFF from '../../codecs/browser-tiff/encoder-meta';
 import * as browserJP2 from '../../codecs/browser-jp2/encoder-meta';
 import * as browserBMP from '../../codecs/browser-bmp/encoder-meta';
-import * as browserPDF from '../../codecs/browser-pdf/encoder-meta';*/
+import * as browserPDF from '../../codecs/browser-pdf/encoder-meta';
 import {
   EncoderState,
   EncoderType,
   EncoderOptions,
-  // encoders,
+  encoders,
   encodersSupported,
   EncoderSupportMap,
 } from '../../codecs/encoders';
 import { QuantizeOptions } from '../../codecs/imagequant/processor-meta';
 import { ResizeOptions } from '../../codecs/resize/processor-meta';
 import { PreprocessorState } from '../../codecs/preprocessors';
-// import FileSize from '../FileSize';
-// import { DownloadIcon } from '../../lib/icons';
+import FileSize from '../FileSize';
+import { DownloadIcon } from '../../lib/icons';
 import { SourceImage } from '../App';
-import Checkbox from './checkbox';
+import Checkbox from '../checkbox';
+import Expander from '../expander';
 
-/*
 const encoderOptionsComponentMap = {
   [identity.type]: undefined,
   [optiPNG.type]: OptiPNGEncoderOptions,
@@ -55,7 +55,7 @@ const encoderOptionsComponentMap = {
   [browserTIFF.type]: undefined,
   [browserJP2.type]: undefined,
   [browserPDF.type]: undefined,
-};*/
+};
 
 interface Props {
   orientation: 'horizontal' | 'vertical';
@@ -125,19 +125,19 @@ export default class Options extends Component<Props, State> {
 
   render(
     {
-      /*source,
+      source,
       imageIndex,
       imageFile,
       downloadUrl,
       orientation,
-      encoderState,*/
+      encoderState,
       preprocessorState,
-      // onEncoderOptionsChange,
+      onEncoderOptionsChange,
     }: Props,
-    // { encoderSupportMap }: State,
+    { encoderSupportMap }: State,
   ) {
     // tslint:disable variable-name
-    // const EncoderOptionComponent = encoderOptionsComponentMap[encoderState.type];
+    const EncoderOptionComponent = encoderOptionsComponentMap[encoderState.type];
 
     return (
       <div class={style.options}>
@@ -148,17 +148,21 @@ export default class Options extends Component<Props, State> {
             checked={!!preprocessorState.resize.enabled}
             onChange={this.onPreprocessorEnabledChange}
           />
-          <span class={style.sectionEnablerLabel}>Resize</span>
+          Resize
         </label>
+        <Expander>
+          {preprocessorState.resize.enabled
+            ?
+              <ResizeOptionsComponent
+                isVector={Boolean(source && source.vectorImage)}
+                aspect={source ? (source.data.width / source.data.height) : 1}
+                options={preprocessorState.resize}
+                onChange={this.onResizeOptionsChange}
+              />
+            : null
+          }
+        </Expander>
         {/*
-        {preprocessorState.resize.enabled &&
-          <ResizeOptionsComponent
-            isVector={Boolean(source && source.vectorImage)}
-            aspect={source ? (source.data.width / source.data.height) : 1}
-            options={preprocessorState.resize}
-            onChange={this.onResizeOptionsChange}
-          />
-        }
         <label class={style.toggle}>
           <input
             name="quantizer.enable"
diff --git a/src/components/Options/style.scss b/src/components/Options/style.scss
index cfa8a80e..9d5f4af9 100644
--- a/src/components/Options/style.scss
+++ b/src/components/Options/style.scss
@@ -16,15 +16,29 @@ $horizontalPadding: 15px;
   border-bottom: 1px solid #000;
 }
 
-.section-enabler {
-  cursor: pointer;
-  background: rgba(0, 0, 0, 0.8);
+.option-text-first {
   display: grid;
-  grid-template-columns: auto 1fr;
-  grid-gap: 0.5em;
-  padding: 6px $horizontalPadding;
+  grid-template-columns: 87px 1fr;
+  grid-gap: 0.7em;
+  padding: 10px $horizontalPadding;
 }
 
-.section-enabler-label {
-  padding-top: 3px;
+.option-input-first,
+.section-enabler {
+  cursor: pointer;
+  display: grid;
+  align-items: center;
+  grid-template-columns: auto 1fr;
+  grid-gap: 0.7em;
+  padding: 10px $horizontalPadding;
 }
+
+.section-enabler {
+  background: rgba(0, 0, 0, 0.8);
+}
+
+.options-section {
+  background: rgba(0, 0, 0, 0.7);
+}
+
+
diff --git a/src/components/Options/checkbox/index.tsx b/src/components/checkbox/index.tsx
similarity index 89%
rename from src/components/Options/checkbox/index.tsx
rename to src/components/checkbox/index.tsx
index bbb97bb4..9ed202ab 100644
--- a/src/components/Options/checkbox/index.tsx
+++ b/src/components/checkbox/index.tsx
@@ -1,6 +1,6 @@
 import { h, Component } from 'preact';
 import * as style from './style.scss';
-import { UncheckedIcon, CheckedIcon } from '../../../lib/icons';
+import { UncheckedIcon, CheckedIcon } from '../../lib/icons';
 
 interface Props extends JSX.HTMLAttributes {}
 interface State {}
diff --git a/src/components/Options/checkbox/style.scss b/src/components/checkbox/style.scss
similarity index 93%
rename from src/components/Options/checkbox/style.scss
rename to src/components/checkbox/style.scss
index 48446237..01ee5b03 100644
--- a/src/components/Options/checkbox/style.scss
+++ b/src/components/checkbox/style.scss
@@ -1,7 +1,7 @@
 .checkbox {
   display: inline-block;
   position: relative;
-  --size: 24px;
+  --size: 17px;
 }
 
 .real-checkbox {
diff --git a/src/components/expander/index.tsx b/src/components/expander/index.tsx
new file mode 100644
index 00000000..b7935110
--- /dev/null
+++ b/src/components/expander/index.tsx
@@ -0,0 +1,90 @@
+import { h, Component, ComponentChild, ComponentChildren } from 'preact';
+import * as style from './style.scss';
+import { linkRef } from '../../lib/initial-util';
+
+interface Props {
+  children: ComponentChildren;
+}
+interface State {
+  outgoingChildren: ComponentChild[];
+}
+
+export default class Expander extends Component<Props, State> {
+  state: State = {
+    outgoingChildren: [],
+  };
+  private el?: HTMLDivElement;
+  private lastElHeight: number = 0;
+
+  componentWillReceiveProps(nextProps: Props) {
+    const children = this.props.children as ComponentChild[];
+    const nextChildren = nextProps.children as ComponentChild[];
+
+    if (!nextChildren[0] && children[0]) {
+      // Cache the current children for the shrink animation.
+      this.setState({ outgoingChildren: children });
+    }
+  }
+
+  componentWillUpdate(nextProps: Props) {
+    const children = this.props.children as ComponentChild[];
+    const nextChildren = nextProps.children as ComponentChild[];
+
+    // Only interested if going from empty to not-empty, or not-empty to empty.
+    if ((children[0] && nextChildren[0]) || (!children[0] && !nextChildren[0])) return;
+    this.lastElHeight = this.el!.getBoundingClientRect().height;
+  }
+
+  componentDidUpdate(previousProps: Props) {
+    const children = this.props.children as ComponentChild[];
+    const previousChildren = previousProps.children as ComponentChild[];
+
+    // Only interested if going from empty to not-empty, or not-empty to empty.
+    if ((children[0] && previousChildren[0]) || (!children[0] && !previousChildren[0])) return;
+
+    // What height do we need to transition to?
+    this.el!.style.transition = 'none';
+    this.el!.style.height = '';
+    const newHeight = children[0] ? this.el!.getBoundingClientRect().height : 0;
+
+    if (this.lastElHeight === newHeight) {
+      this.el!.style.transition = '';
+      return;
+    }
+
+    // Set the currently rendered height absolutely.
+    this.el!.style.height = this.lastElHeight + 'px';
+    this.el!.style.transition = '';
+    // Force a style calc so the browser picks up the start value.
+    getComputedStyle(this.el!).height;
+    // Animate to the new height.
+    this.el!.style.height = newHeight + 'px';
+
+    const listener = () => {
+      // Unset the height, so element changes do the right thing.
+      this.el!.style.height = '';
+      this.el!.removeEventListener('transitionend', listener);
+      this.el!.removeEventListener('transitioncancel', listener);
+      if (this.state.outgoingChildren[0]) {
+        this.setState({ outgoingChildren: [] });
+      }
+    };
+
+    this.el!.addEventListener('transitionend', listener);
+    this.el!.addEventListener('transitioncancel', listener);
+  }
+
+  render(props: Props, { outgoingChildren }: State) {
+    const children = props.children as ComponentChild[];
+    const childrenExiting = !children[0] && outgoingChildren[0];
+
+    return (
+      <div
+        ref={linkRef(this, 'el')}
+        class={`${style.expander} ${childrenExiting ? style.childrenExiting : ''}`}
+      >
+        {children[0] ? children : outgoingChildren}
+      </div>
+    );
+  }
+}
diff --git a/src/components/expander/style.scss b/src/components/expander/style.scss
new file mode 100644
index 00000000..2f0dabb9
--- /dev/null
+++ b/src/components/expander/style.scss
@@ -0,0 +1,10 @@
+.expander {
+  overflow: hidden;
+  transition: height 200ms ease-in-out;
+}
+
+.children-exiting {
+  & > * {
+    pointer-events: none;
+  }
+}
diff --git a/src/lib/icons.tsx b/src/lib/icons.tsx
index 2790b410..534972d3 100644
--- a/src/lib/icons.tsx
+++ b/src/lib/icons.tsx
@@ -32,12 +32,12 @@ export const RemoveIcon = (props: JSX.HTMLAttributes) => (
 
 export const UncheckedIcon = (props: JSX.HTMLAttributes) => (
   <Icon {...props}>
-    <path d="M19 5v14H5V5h14m0-2H5a2 2 0 0 0-2 2v14c0 1.1.9 2 2 2h14a2 2 0 0 0 2-2V5a2 2 0 0 0-2-2z"/>
+    <path d="M21.3 2.7v18.6H2.7V2.7h18.6m0-2.7H2.7A2.7 2.7 0 0 0 0 2.7v18.6A2.7 2.7 0 0 0 2.7 24h18.6a2.7 2.7 0 0 0 2.7-2.7V2.7A2.7 2.7 0 0 0 21.3 0z"/>
   </Icon>
 );
 
 export const CheckedIcon = (props: JSX.HTMLAttributes) => (
   <Icon {...props}>
-    <path d="M19 3H5a2 2 0 0 0-2 2v14c0 1.1.9 2 2 2h14a2 2 0 0 0 2-2V5a2 2 0 0 0-2-2zm-9 14l-5-5 1.4-1.4 3.6 3.6 7.6-7.6L19 8l-9 9z"/>
+    <path d="M21.3 0H2.7A2.7 2.7 0 0 0 0 2.7v18.6A2.7 2.7 0 0 0 2.7 24h18.6a2.7 2.7 0 0 0 2.7-2.7V2.7A2.7 2.7 0 0 0 21.3 0zm-12 18.7L2.7 12l1.8-1.9L9.3 15 19.5 4.8l1.8 1.9z"/>
   </Icon>
 );