> For the complete documentation index, see [llms.txt](https://docs.apryse.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.apryse.com/web/get-started/samples/fast-viewing.md).

# Viewer optimized PDFs

See a side-by-side comparison of a PDF viewer rendering an unoptimized PDF vs an optimized PDF using this JavaScript sample. Optimized PDFs render in viewers faster, giving users access to even large

See a side-by-side comparison of a PDF viewer rendering an unoptimized PDF vs an optimized PDF using this JavaScript sample. Optimized PDFs render in viewers faster, giving users access to even large and complex PDF documents in seconds. This sample works on all browsers (including IE11) and mobile devices without using plug-ins. Learn more about our [Web SDK](/web/get-started/guides.md).

{% tabs %}
{% tab title="JavaScript" %}
{% code lineNumbers="true" %}

```js
const FILES = {
  'demo-annotated.pdf': ['../../../samples/files/demo-annotated-non-optimized.pdf', '../../../samples/files/demo-annotated.pdf'],
  'construction-drawing-final.pdf': ['../../../samples/files/construction-drawing-final.pdf', '../../../samples/files/construction-drawing-optimized.pdf'],
  'cheetahs.pdf': ['../../../samples/files/cheetahs-non-optimized.pdf', '../../../samples/files/cheetahs.pdf'],
  'magazine.pdf': ['https://pdftron.s3.amazonaws.com/downloads/pl/magazine.pdf', 'https://pdftron.s3.amazonaws.com/downloads/pl/magazine-optimized.pdf'],
  'webviewer-demo.pdf': ['https://pdftron.s3.amazonaws.com/downloads/pl/webviewer-demo.pdf', 'https://pdftron.s3.amazonaws.com/downloads/pl/webviewer-demo-optimized.pdf'],
};

const _selected = localStorage.getItem('__selectedFiles');
const _selectedFiles = FILES[_selected];

const firstPdf = _selectedFiles ? _selectedFiles[0] : null;
const secondPdf = _selectedFiles ? _selectedFiles[1] : null;
const firstPdfUrl = localStorage.getItem('__firstPdfUrl');
const secondPdfUrl = localStorage.getItem('__secondPdfUrl');
const isFullAPI = localStorage.getItem('__isFullAPI') || false;

let sourceOne;
let sourceTwo;

if (firstPdfUrl && secondPdfUrl) {
  document.getElementById('url').value = firstPdfUrl;
  document.getElementById('url2').value = secondPdfUrl;
  sourceOne = firstPdfUrl;
  sourceTwo = secondPdfUrl;

  document.getElementById('select1').value = undefined;
} else {
  const defaultSelected = 'cheetahs.pdf';
  const _selectedFiles = FILES[defaultSelected];
  sourceOne = firstPdf || _selectedFiles[0];
  sourceTwo = secondPdf || _selectedFiles[1];

  document.getElementById('select1').value = _selected || defaultSelected;
}
document.getElementById('isFullAPI').checked = isFullAPI;

const timerOne = Date.now();
const timerTwo = Date.now();

// ============== WebViewer setup =============
WebViewer(
  {
    path: '../../../lib',
    initialDoc: sourceOne,
    fullAPI: isFullAPI,
  },
  document.getElementById('middlePanel')
).then(instance => {
  instance.Core.documentViewer.addEventListener('documentLoaded', () => {
    const timerOneFinish = Date.now();
    console.log('The first viewer', timerOneFinish - timerOne);
  });
});

WebViewer(
  {
    path: '../../../lib',
    initialDoc: sourceTwo,
    fullAPI: isFullAPI,
  },
  document.getElementById('leftPanel')
).then(instance => {
  instance.Core.documentViewer.addEventListener('documentLoaded', () => {
    const timerTwoFinish = Date.now();
    console.log('The second viewer', timerTwoFinish - timerTwo);
  });
});

// ============== End WebViewer setup =============

// ============== Setup input controllers =============
document.getElementById('selectControl').onclick = e => {
  e.preventDefault();
  const select1 = document.getElementById('select1');
  const selected = select1.options[select1.selectedIndex].value;

  localStorage.setItem('__selectedFiles', selected);
  localStorage.removeItem('__firstPdfUrl');
  localStorage.removeItem('__secondPdfUrl');
  location.reload();
};

document.getElementById('url-form').onsubmit = e => {
  e.preventDefault();
  const firstPdf = document.getElementById('url').value;
  const secondPdf = document.getElementById('url2').value;

  localStorage.setItem('__firstPdfUrl', firstPdf);
  localStorage.setItem('__secondPdfUrl', secondPdf);

  localStorage.removeItem('__selectedFiles');
  location.reload();
};

document.getElementById('isFullAPI').onchange = e => {
  if (e.target.checked) {
    localStorage.setItem('__isFullAPI', true);
  } else {
    localStorage.removeItem('__isFullAPI');
  }
};
```

{% endcode %}
{% endtab %}
{% endtabs %}


---

# Agent Instructions
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Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:

```
GET https://docs.apryse.com/web/get-started/samples/fast-viewing.md?ask=<question>&goal=<user_goal>
```

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