Caching Information in <META> Tag

Issue Summary

This web page is using the <meta> tag to specify how the document should be cached. The vast majority of caching proxies and some web browsers do examine the body on an HTTP response for caching information. Instead only the HTTP headers are examined for caching information. You should remove these <meta> tags and ensure that HTTP header convey the appropriate caching information. This will decrease web page size and bandwidth consumption with the potential of significantly reducing web server load.

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Affected URLs

JPEG Candidate Image (GIF)

Issue Summary

This unanimated image uses the GIF image format. Converting this GIF image to a JPEG formatted image would reduce its size by over 35%. Since the GIF format has different features and advantages than the JPEG format (such as fixed color palettes and Boolean transparency) you should evaluate each image to determine if it should be converted. Since converting to JPEG yields such a large saving you should make every effort to do so where appropriate. Converting these GIF images to JPEG images will improve page load times while reducing bandwidth consumption.

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Savings Table

JPEG Candidate Image (PNG)

Issue Summary

This image uses the PNG image format. Converting this PNG image to a JPEG formatted image would reduce its size by over 35%. Since the PNG format has different features and advantages than the JPEG format (such as alpha transparency and sharp edges) you should evaluate each image to determine if it should be converted. Since converting to JPEG yields such a large saving you should make every effort to do so where appropriate. Converting these PNG images to JPEG images will improve page load times while reducing bandwidth consumption.

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Single Color Image

Issue Summary

This image consists of only a single color. In most cases this entire image can be replaced using a background color. Replacing this image with a background color would completely eliminate the need to request this image which would decrease bandwidth consumption and improve page load times.

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Affected URLs

Unoptimized Image (Animated GIF)

Issue Summary

This animated GIF image can be further optimized to reduce the file size without reducing image quality. This will improve server performance while decreasing bandwidth consumption.

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Unoptimized Image (GIF)

Issue Summary

This GIF image contains extra data such as comments and unused palette entries and also uses an older graphics compression technology. This image can be further optimized using free tools that will reduce the size of the file without changing or reducing the image quality. These image optimizations are especially important as other optimizations, such as HTTP compression, cannot be applied to images. Optimizing this image will improve server performance while decreasing bandwidth consumption and page load times.

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Unoptimized Image (JPG)

Issue Summary

This JPG image can be further optimized to reduce the file size without reducing image quality. This will improve server performance while decreasing bandwidth consumption.

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Unoptimized Image (PNG)

Issue Summary

This PNG image is needlessly large. This is due to extra data inside the PNG file such as comments or unused palette entries as well as the use of an inefficient DEFLATE compressor. This image can optimized using free tools that would reduce the size of the file without changing or reducing the image quality. These image optimizations are especially important as other optimizations, such as HTTP compression, cannot be applied to images. Optimizing this PNG image will improve server performance while decreasing bandwidth consumption and page load times.

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Unoptimized Image (Progressive JPG)

Issue Summary

This JPG image is needlessly large. By converting this JPG to a progressively rendered JPG you can reduce the size of the file without losing image quality. This will improve server performance and page load times while decreasing bandwidth consumption.

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Combinable JavaScript Libraries

Issue Summary

This webpage contains multiple <script src> tags which reference external JavaScript files on the same hostname and sometimes even in the same directory. As such it appears many of these external JavaScript files can be safely combined into a single JavaScript file. By combining multiple external JavaScript files into a single JavaScript file you will reduce the number of HTTP requests the browser has to make to render this web page. Combining these JavaScript files can drastically improve web server performance and page load times while reducing bandwidth consumption.

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Affected URLs

Combinable Style Sheets

Issue Summary

This web page contains multiple <link> tags which reference external Cascading Style Sheets. These Cascading Style Sheets can be safely combined into only a handful of Cascading Style Sheets files. By combining multiple CSS files into a single CSS file you will reduce the number of HTTP requests the browser has to make to render this web page. Combining these CSS files will drastically improve web server performance and page load times while reducing bandwidth consumption.

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Affected URLs

Combinable CSS Images

Issue Summary

This resource contains style information will too many individual background images. The browser must make an HTTP request for each background image that is used when rendering the web page. It is not uncommon for over half of all HTTP requests made for page resources to be for CSS background images. You can combine nearly all these background images into a handful of CSS Sprites. This will reduce the number of HTTP requests required to load this page which can significantly improve page load times while reducing web server load and bandwidth consumption.

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Affected URLs

Domain Sharding Not Implemented

Issue Summary

This page does not use multiple domain names to take advantage of parallel downloading. Parallel downloading allows the browser to download all the resources that make up a web page faster by downloading them in parallel from multiple hostnames. This will improve page load times.

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Affected URLs

Duplicate Resource (Image)

Issue Summary

This image is identical to another image on the website but both pages are referenced using different URLs. Unfortunately, because the URLs are different, a visitor's web browser must request this image even though it might already have an identical copy of the image cached under a different URL. Duplicate content served from different URLs can also negatively affect search engine rankings. You should remove this duplicate image and use a single, consistent URL to reference the image.

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Affected URLs

Excessive HTML Comments

Issue Summary

A large HTML comment was detected on this web page. HTML comments are not displayed or shown to a user, nor or they processed by Search engine spiders. As such, they add to the size of the page without adding any user experience or SEO value. HTML comments are often used with templating systems. Large HTML comments should be removed to improve page load time while reducing file size and bandwidth consumption.

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Affected URLs

High Quality JPEG Image

Issue Summary

This JPEG image was saved with a quality setting greater than 80. JPEG images use a variable level of quality, the higher the number the greater the quality but the larger the file size. However this setting can be deceptive. A quality rating of 90 does not mean "keep 90% of the graphical data." The quality scale is purely arbitrary; it's not a percentage of anything. A general guideline for JPEG images on the web is to use a quality rating of 50-75. This quality range is a good compromise between image quality and file size. Reducing this high quality JPEG will reduce file size, which will decrease bandwidth consumption and improve page load times.

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Image Tags Without Dimensions

Issue Summary

This web page contains <img> tags which are not using height or width attributes. If the browser knows the height and width of an image before it downloads and renders the image it can continue to render the web page. If the browser does not know the image size it must redraw the web page again after the image downloads. Adding height or width attributes will make this web page render faster.

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Affected URLs

Image Without Far Future Caching Information

Issue Summary

The response for this image contains HTTP caching information that allows it to be unconditionally cached on the client. However, this HTTP caching information instructs a visitor's browser to store the image for less than 4 months. Static content like images should be cached until a far future date, typically 6 months to a year, as it rarely changes and when it does change the content's URL changes as well. Using HTTP caching with this image for a date far into the future will reduce the load on the web server, while significantly reducing both bandwidth consumption and page load times.

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Affected URLs

JavaScript Debugging Statements (console.log())

Issue Summary

This resource contains JavaScript code with debugging functions. Specifically this code contains call to the console.log() function. This function is useful during development to aid in debugging. However it should not appear in production code for several reasons: it increases the size of this response; it causes a runtime performance penalty; and it can cause runtime error messages in browser which do not have a console object. Removing code that uses console.log() will slightly improve performance for this response.

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Affected URLs

JavaScript Not Minified (External File)

Issue Summary

This page contains JavaScript code that has not been minified. Minifying JavaScript reduces the size of the JavaScript allowing the browser to download, parse, and execute the code faster. This will improve application performance by decreasing page load time, bandwidth consumption, and web server load.

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Script Without Far Future Caching Information

Issue Summary

The response for this JavaScript file contains HTTP caching information that allows it to be unconditionally cached on the client. However, this HTTP caching information instructs a visitor's browser to store the JavaScript file for less than 4 months. Static content like JavaScript files should be cached until a far future date, typically 6 months to a year, as it rarely changes and when it does change the content's url changes as well. Using HTTP caching with this JavaScript file for a date far into the future will reduce the load on the web server, while significantly reducing both bandwidth consumption and page load times.

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Affected URLs

Session State detected in URL

Issue Summary

This response contains hyperlinks with application session state embedded inside of the URL. This is a common technique of application frameworks like ASP.NET or J2EE to maintain session state if the visitor has disabled cookies in their browser. However this increases the size of every hyperlink in the application and creates a security issue. Disabling in-URL session state will decrease bandwidth consumption, improve page load times, and enhance application security.

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Affected URLs

Shared Caching Disabled for JavaScript (Query String)

Issue Summary

The URL for this JavaScript file contains a query string. Query strings are not typically needed when serving static resources like images, style sheets, or scripts. HTTP caches typically will not cache any resource whose URL contains a query string. Removing the query string from the resource's URL will allow caching proxies or load balancers that you own and downstream caching proxies to serve this resource for you significantly reducing web server load and bandwidth consumption.

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Affected URLs

Style Sheet Without Far Future Caching Information

Issue Summary

The response for this style sheet contains HTTP caching information that allows it to be unconditionally cached on the client. However, this HTTP caching information instructs a visitor's browser to store the style sheet for less than 4 months. Static content like style sheets should be cached until a far future date, typically 6 months to a year, as it rarely changes and when it does change the content's url changes as well. Using HTTP caching with this style sheet for a date far into the future will reduce the load on the web server, while significantly reducing both bandwidth consumption and page load times.

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Affected URLs

Unoptimized External CSS Resource Location

Issue Summary

This page contains a <link> tag to an external style sheet which is in a suboptimal location in the HTML. <link> tags to Cascading Style Sheets should be located at the top of the web page. This allows the browser to know how to style the elements of the web page before it starts to draw them. Many browser will not draw anything on the web page until the CSS has been downloaded, reducing the client-side performance and user experience for your application.

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Affected URLs

Unoptimized Resource Location (JavaScript)

Issue Summary

This page contains a reference to a external JavaScript file in a suboptimal location. Specifically it contains a <script src> tag that is not in the bottom 20% of the HTML. Browsers stop drawing the page and will not download any other files when they encounter JavaScript code. Moving <script src> tags to the bottom of the web page will improve client-side performance.

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Affected URLs

Unused inline Style

Issue Summary

This page declares several CSS styles inside of a <style> tag but does not use those styles on this page.

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Affected URLs

Dynamic HTML Not Minified

Issue Summary

This web page contains HTML that has not been minified. HTML can contain extra whitespace, comments, unrecognized HTML tags, unminified JavaScript code in <script> tags, and unminified CSS data in <style> tags. For this web page, minifying the HTML will reduce the size of the page by more than 5%. Since this appears to be a dynamically generated web page, you should minify the template used by your application for this page. This solution will reduce bandwidth consumption while improving page load times.

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PNG8 Candidate Image (Color Count)

Issue Summary

This true color PNG image contains less than 2500 distinct colors. Converting this image from a true color PNG to a palette-based PNG (also called a PNG8) should significantly reduce the size of the image. While PNG8 will not have as many distinct colors as the original image this difference is not usually noticeable for images with less than 2500 distinct colors. Converting this image to a PNG8 will reduce bandwidth consumption and improve page load speeds.

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PNG8 Candidate Image (Pixel Area)

Issue Summary

This true color PNG image has a pixel area less than 100 pixels by 100 pixels. Converting this image from a true color PNG to a palette-based PNG (also called a PNG8) should significantly reduce the size of the image. While PNG8 will not have as many distinct colors as the original image this difference should not be noticeable on such a small sized image. Converting this image to a PNG8 will reduce bandwidth consumption and improve page load speeds.

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Missing HTTP Accept-Ranges Header (JavaScript)

Issue Summary

The response for this JavaScript file does not contain an Accept-Ranges header. The Accept-Ranges header allows browsers to recover from connection errors and timeouts and without having to redownload all of the content that was downloaded before the error occurred. Since connections errors and timeouts usually occur when a web server is under heavy load, Accept-Ranges helps reduce the stress on the server and lessen the number of connections and bandwidth requirements of incoming requests. Often server responses for JavaScript files will be missing an Accept-Ranges header when the JavaScript file is dynamically generated. You should identify the cause of the missing Accept-Ranges header and reconfigure your web application to add an Accept-Ranges header. This solution will reduce web server load and improve website performance.

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Affected URLs

<SCRIPT SRC> Without Defer

Issue Summary

This web page contains a <script src> tag which loads an external JavaScript file but it does not use a defer attribute. Using the defer attribute is an easy way to enable parallel downloading of resource for older web browsers like Internet Explorer 7 and Firefox 3.1. If appropriate, you can use the defer attribute to tell the browser it does not need to stop and wait for this external script file to load before downloading or rendering more content. Care must be taken later <script> blocks may use code in deferred <script src> blocks. Solving this issue will improve page load times and client-side performance.

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Affected URLs

<STYLE> Tag Not in <HEAD>

Issue Summary

This page contains a <style> tag which is not located in the <head> tag. Placing <style> tags at the top of the web page allows the browser to know how to style the elements of the web page before it starts to draw them. Many browsers will not draw anything on the web page until the style information has been processed. Moving the <style> tag to the top of the HTML file will help improve client-side performance by allowing the browser to render the appropriate styles faster.

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Affected URLs

Adjacent <STYLE> Tags

Issue Summary

This web page contains <style> tags containing CSS information that are adjacent to each other. These multiple consectutive <style> tags can be combined into a single <style> tag to slight reduce page size and bandwidth consumption.

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Affected URLs

Cookies Sent for Component (CSS)

Issue Summary

The request for this static CSS file contains HTTP cookies. There is no reason to sends cookies when requesting a static resource. This increases the size of the HTTP request and can also prevent downstream caches from storing the object. You should serve your static resources from a cookie-less domain, or use the domain or path attribute for cookies to limit their scope. Properly configuring your cookies will improve client-side performance and page load times while decreasing bandwidth consumption and web server load.

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Affected URLs

Cookies Sent for Component (Image)

Issue Summary

The request for this static image contains HTTP cookies. There is no reason to sends cookies when requesting a static resource. This increases the size of the HTTP request and can also prevent downstream caches from storing the object. You should serve your static resources from a cookie-less domain, or use the domain or path attribute for cookies to limit their scope. Properly configuring your cookies will improve client-side performance and page load times while decreasing bandwidth consumption and web server load.

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Affected URLs

Cookies Sent for Component (JavaScript)

Issue Summary

The request for this static JavaScript file contains HTTP cookies. There is no reason to sends cookies when requesting a static resource. This increases the size of the HTTP request and can also prevent downstream caches from storing the object. You should serve your static resources from a cookie-less domain, or use the domain or path attribute for cookies to limit their scope. Properly configuring your cookies will improve client-side performance and page load times while decreasing bandwidth consumption and web server load.

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Affected URLs

CSS Mixed Media Types (@media)

Issue Summary

This resource contains CSS instructions which uses the @media directive to mix styling information for multiple different media types together. This increases the size of the CSS for media types that may or may not get used. Styling information for specific media types should be placed in its own external CSS file so that only users who need it will have to download it. Making this change with decrease bandwidth consumption and improve page load times.

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Affected URLs

CSS Not Minified (<STYLE> Block)

Issue Summary

This page contains a <style> block with style information that has not been minified. Minifying style information reduces the size of the content, allowing for faster download and parsing.

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Affected URLs

JavaScript Not Minified (<SCRIPT> Block)

Issue Summary

This page contains a <script> tag containing JavaScript code that has not been minified. Minifying JavaScript reduces the size of the JavaScript, allowing for faster download and parsing while decreasing bandwidth and server loads.

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Affected URLs

Permanent HTTP Redirect without Caching

Issue Summary

This 301 redirect does not containing caching information allowing a browser to cache the redirect. Modern browser can cache redirects, allowing a user to more quickly access the final page content. If this is truly a permanent redirect you should add a far future Expires or Cache-Control header. Doing so will reduce page load times and slightly reduce bandwidth consumption.

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Affected URLs

Unnecessary HTTP Caching Header (Pragma)

Issue Summary

This response is using the HTTP header Pragma to attempt to control caching. Most caching proxies and some web browsers do not use the Pragma header to determine caching information. Since this response also uses the Expires or Cache-Control HTTP header the Pragma header is unnecessary. Removing the Pragma header from this response will slightly decrease bandwidth consumption.

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Affected URLs

Excessive Absolute URLs (Same Site)

Issue Summary

This web page contains a large number of references and hyperlinks to resources on the same host using absolute URLs. Each absolute URLs includes the protocol, hostname, and port number as well as the typical path, filename, and query string information. Since this web page is referenced using the same protocol, hostname, and port number that the absolute URLs use these URLs can be converted from absolute URLs into relative URLs without any loss of functionality. This solution would reduce web page size and bandwidth consumption.

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Affected URLs

Excessive Hidden Inputs (Number)

Issue Summary

This page contains over eight <input type="hidden"> tags. This increases the size of the web page as well as requests from the client for web form submissions. Consider removing or consolidating these fields into a smaller number of hidden inputs or store some of this data on the server in session oriented storage. This will decrease page load time and bandwidth consumption.

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Affected URLs

JavaScript Dynamic Compilation (eval)

Issue Summary

This resource contains JavaScript code that is using the eval() function. JavaScript's eval() function is used to dynamically compile and execute JavaScript code that is stored in a string. This process is expensive and generally it should be avoided. Avoiding the use of eval() will improve client-side performance.

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Affected URLs

Excessive DOM Size

Issue Summary

This web page contains more than 700 HTML tags. This is an excessive DOM size which reduces page load times and the performance of client-side JavaScript. Excessive DOMs usually indict other problems such as poor design or table-based layouts. As a benchmark, Yahoo's homepage has less than 700 DOM elements. Consider reducing the number of DOM elements to improve performance.

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Affected URLs

Uncacheable Response (iPhone)

Issue Summary

The iPhone is only able to cache web server responses whose uncompressed size is less than 15 Kilobytes. This response is greater than 20K. There is no easy way to make this response small enough to be cached by the iPhone. If this is an important resource that should be cached you should redesign the resource so it is small enough to be cached. Caching responses on the iPhone will reduce web server load and improve page load speeds for iPhone visitors.

Affected URLs

WebP Candidate Image

Issue Summary

This JPEG image could be converted to a WebP image that is over 50% smaller. WebP is a new image format created by Google and is only supported by the Chrome and Opera web browsers. If you wanted to convert this image, you would need to configure you web server or application to serve a different image for browsers that support WebP. The best solution would be to implement this logic so that the URL for this image can be rewritten to point to the WebP version of the image. This ensures there will be no caching problems.

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