openintro.org Website Information

Daily Unique Visits: 6,966

Daily Page Views: 34,830

Income Per Day: $87

Estimated Value: $52,200

openintro.org is registered under .ORG top-level domain. Please check other sites in .ORG zone.

No name server records were found.

and is probably hosted by NETWORK-SOLUTIONS-HOSTING - Network Solutions, LLC, US. See the full list of other websites hosted by NETWORK-SOLUTIONS-HOSTING - Network Solutions, LLC, US.

The highest website openintro.org position in Alexa rank database was 24602 and the lowest rank position was 993466. Current position of openintro.org in Alexa rank database is 195591.

Desktop speed score of openintro.org (77/100) is better than the results of 63.93% of other sites and shows that the page desktop performance can be improved.

Mobile usability score of openintro.org (82/100) is better than the results of 26.06% of other sites and means that the page is mobile-friendly.

Mobile speed score of openintro.org (65/100) is better than the results of 66.06% of other sites and shows that the landing page performance on mobile devices is poor and can be improved.

openintro.org Alexa Rank

The traffic rank is based on three months of aggregated historical traffic data from millions of Alexa Toolbar users and is a combined measure of page views and users.

openintro.org whois

WHOIS gives you the ability to lookup any generic domains to find out the registered domain holder. WHOIS database are provided for information purposes only. It allows the public to check whether a specific domain name is still available or not and to obtain information related to the registration records of existing domain names.

Domain Name: openintro.org
Registry Domain ID: 7872da639ab14358a559d74471b6aa37-LROR
Registrar WHOIS Server: whois.squarespace.domains
Registrar URL: https://domains.squarespace.com
Updated Date: 2024-05-18T06:58:09Z
Creation Date: 2009-07-11T19:22:08Z
Registry Expiry Date: 2032-07-11T19:22:08Z
Registrar: Squarespace Domains II LLC
Registrar IANA ID: 895
Registrar Abuse Contact Email: abuse-complaints@squarespace.com
Registrar Abuse Contact Phone: +1.6466935324
Domain Status: clientDeleteProhibited https://icann.org/epp#clientDeleteProhibited
Domain Status: clientTransferProhibited https://icann.org/epp#clientTransferProhibited
Registry Registrant ID: REDACTED FOR PRIVACY
Registrant Name: REDACTED FOR PRIVACY
Registrant Organization:
Registrant Street: REDACTED FOR PRIVACY
Registrant City: REDACTED FOR PRIVACY
Registrant State/Province: MN
Registrant Postal Code: REDACTED FOR PRIVACY
Registrant Country: US
Registrant Phone: REDACTED FOR PRIVACY
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Registrant Fax: REDACTED FOR PRIVACY
Registrant Fax Ext: REDACTED FOR PRIVACY
Registrant Email: Please query the RDDS service of the Registrar of Record identified in this output for information on how to contact the Registrant, Admin, or Tech contact of the queried domain name.
Registry Admin ID: REDACTED FOR PRIVACY
Admin Name: REDACTED FOR PRIVACY
Admin Organization: REDACTED FOR PRIVACY
Admin Street: REDACTED FOR PRIVACY
Admin City: REDACTED FOR PRIVACY
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Admin Email: Please query the RDDS service of the Registrar of Record identified in this output for information on how to contact the Registrant, Admin, or Tech contact of the queried domain name.
Registry Tech ID: REDACTED FOR PRIVACY
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Tech Organization: REDACTED FOR PRIVACY
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Tech Email: Please query the RDDS service of the Registrar of Record identified in this output for information on how to contact the Registrant, Admin, or Tech contact of the queried domain name.
Name Server: ns1629.hostgator.com
Name Server: ns1630.hostgator.com
DNSSEC: unsigned
URL of the ICANN Whois Inaccuracy Complaint Form: https://www.icann.org/wicf/
>>> Last update of WHOIS database: 2024-10-21T03:47:35Z

openintro.org server information

Servers Location

openintro.org desktop page speed rank

Last tested: 2018-12-09

Desktop Speed Medium

77/100

openintro.org Desktop Speed Test Quick Summary

priority - 10Eliminate render-blocking JavaScript and CSS in above-the-fold content

Your page has 2 blocking script resources and 2 blocking CSS resources. This causes a delay in rendering your page.

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https://www.openintro.org/pp/plugins/angular.min_1.5.3.js

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https://www.openintro.org/pp/cssGeneral007.css

priority - 9Optimize images

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priority - 7Leverage browser caching

Setting an expiry date or a maximum age in the HTTP headers for static resources instructs the browser to load previously downloaded resources from local disk rather than over the network.

Leverage browser caching for the following cacheable resources:

https://www.openintro.org/img/brand/bg.png (expiration not specified)
https://www.openintro.org/img/brand/oiLogo_highres.png (expiration not specified)
https://www.openintro.org/img/brand/openintro_home…_graphics_20160402.png (expiration not specified)
https://www.openintro.org/img/grid/whiteBoxTransparentGrid.png (expiration not specified)
https://www.openintro.org/img/socialmedia/icons/icons_001.png (expiration not specified)
https://www.openintro.org/img/subjects/statOverview_001.png (expiration not specified)
https://www.openintro.org/img/subjects/statOverview_002.png (expiration not specified)
https://www.openintro.org/pp/css013.css (expiration not specified)
https://www.openintro.org/pp/cssGeneral007.css (expiration not specified)
https://www.openintro.org/pp/plugins/angular.min_1.5.3.js (expiration not specified)
https://www.openintro.org/pp/plugins/dragsort002.js (expiration not specified)
https://www.openintro.org/pp/plugins/jquery_validate_001.js (expiration not specified)
https://www.openintro.org/pp/plugins/jsCore003.js (expiration not specified)
https://use.typekit.net/stg1oei.js (10 minutes)
https://www.google-analytics.com/analytics.js (2 hours)

priority - 1Reduce server response time

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openintro.org Desktop Resource Breakdown

Total Resources	35
Number of Hosts	8
Static Resources	20
JavaScript Resources	10
CSS Resources	2

openintro.org mobile page speed rank

Last tested: 2018-12-09

Mobile Speed Medium

65/100

openintro.org Mobile Speed Test Quick Summary

priority - 40Eliminate render-blocking JavaScript and CSS in above-the-fold content

Your page has 2 blocking script resources and 2 blocking CSS resources. This causes a delay in rendering your page.

Remove render-blocking JavaScript:

https://use.typekit.net/stg1oei.js
https://www.openintro.org/pp/plugins/angular.min_1.5.3.js

Optimize CSS Delivery of the following:

https://www.openintro.org/pp/css013.css
https://www.openintro.org/pp/cssGeneral007.css

priority - 11Leverage browser caching

Setting an expiry date or a maximum age in the HTTP headers for static resources instructs the browser to load previously downloaded resources from local disk rather than over the network.

Leverage browser caching for the following cacheable resources:

https://www.openintro.org/img/brand/bg_hd.png (expiration not specified)
https://www.openintro.org/img/brand/oiLogo_highres.png (expiration not specified)
https://www.openintro.org/img/brand/openintro_home…_graphics_20160402.png (expiration not specified)
https://www.openintro.org/img/grid/whiteBoxTransparentGrid.png (expiration not specified)
https://www.openintro.org/img/socialmedia/icons/icons_001.png (expiration not specified)
https://www.openintro.org/img/subjects/statOverview_001.png (expiration not specified)
https://www.openintro.org/img/subjects/statOverview_002.png (expiration not specified)
https://www.openintro.org/pp/css013.css (expiration not specified)
https://www.openintro.org/pp/cssGeneral007.css (expiration not specified)
https://www.openintro.org/pp/plugins/angular.min_1.5.3.js (expiration not specified)
https://www.openintro.org/pp/plugins/dragsort002.js (expiration not specified)
https://www.openintro.org/pp/plugins/jquery_validate_001.js (expiration not specified)
https://www.openintro.org/pp/plugins/jsCore003.js (expiration not specified)
https://use.typekit.net/stg1oei.js (10 minutes)
https://www.google-analytics.com/analytics.js (2 hours)

priority - 3Optimize images

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Compressing https://www.openintro.org/img/subjects/statOverview_002.png could save 19.2KiB (42% reduction).
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Compressing https://www.openintro.org/img/brand/oiLogo_highres.png could save 5.2KiB (26% reduction).
Compressing https://www.openintro.org/img/brand/bg_hd.png could save 1.7KiB (46% reduction).
Compressing https://www.openintro.org/img/grid/whiteBoxTransparentGrid.png could save 742B (90% reduction).

priority - 0Minify JavaScript

Compacting JavaScript code can save many bytes of data and speed up downloading, parsing, and execution time.

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priority - 0Reduce server response time

In our test, your server responded in 0.23 seconds.

priority - 0Minify CSS

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Minify CSS for the following resources to reduce their size by 1.9KiB (24% reduction).

priority - 0Minify HTML

Compacting HTML code, including any inline JavaScript and CSS contained in it, can save many bytes of data and speed up download and parse times.

Minify HTML for the following resources to reduce their size by 399B (13% reduction).

Minifying https://www.openintro.org/ could save 399B (13% reduction) after compression.

openintro.org Mobile Resource Breakdown

Total Resources	35
Number of Hosts	8
Static Resources	20
JavaScript Resources	10
CSS Resources	2

openintro.org mobile page usability

Last tested: 2018-12-09

Mobile Usability Medium

82/100

openintro.org Mobile Usability Test Quick Summary

priority - 10Configure the viewport

Your page does not have a viewport specified. This causes mobile devices to render your page as it would appear on a desktop browser, scaling it down to fit on a mobile screen. Configure a viewport to allow your page to render properly on all devices.

priority - 6Size tap targets appropriately

Some of the links/buttons on your webpage may be too small for a user to easily tap on a touchscreen. Consider making these tap targets larger to provide a better user experience.

The following tap targets are close to other nearby tap targets and may need additional spacing around them.

The tap target <a href="/index.php" class="oiLogo"></a> is close to 1 other tap targets.

The tap target <a href="/redirect.php?…rer=/index.php" class="socialMediaIconContainerSmall"></a> and 2 others are close to other tap targets.

The tap target <a href="/stat" class="mmenu">Products</a> is close to 1 other tap targets.

The tap target <div id="dot_1" class="panel_control_…control_dot_on"> is close to 3 other tap targets.

The tap target <div id="dot_2" class="panel_control_dot"> and 1 others are close to other tap targets.

priority - 5Use legible font sizes

The following text on your page renders in a way that may be difficult for some of your visitors to read. Use legible font sizes to provide a better user experience.

The following text fragments have a small font size. Increase the font size to make them more legible.

CONTRIBUTE and 4 others render only 5 pixels tall (12 CSS pixels).

LOG IN renders only 4 pixels tall (11 CSS pixels).

IS BEST FOR YO…YOUR STUDENTS. and 1 others render only 5 pixels tall (13 CSS pixels).

PRACTICE and 1 others render only 5 pixels tall (12 CSS pixels).

Learn statisti…never outgrow and 1 others render only 5 pixels tall (12 CSS pixels).

CLICK HERE TO EXPLORE and 1 others render only 4 pixels tall (11 CSS pixels).

TERMS renders only 5 pixels tall (12 CSS pixels).

openintro.org HTML validation

Errors

A “meta” element with an “http-equiv” attribute whose value is “X-UA-Compatible” must have a “content” attribute with the value “IE=edge”.

Line: 3 Column: 2 - 63
"..."utf-8"> <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1"> <scr..."

An “img” element must have an “alt” attribute, except under certain conditions. For details, consult guidance on providing text alternatives for images.

Line: 17 Column: 6 - 70
"...go"> <img src="/img/brand/oiLogo_highres.png" height="82" width="157"></a> ..." Line: 23 Column: 7 - 131
"...k"> <img id="twitter_small" class="socialMediaIconSmall" height="129px" width="174px" src="/img/socialmedia/icons/icons_001.png"> <..." Line: 28 Column: 7 - 131
"...k"> <img id="youtube_small" class="socialMediaIconSmall" height="129px" width="174px" src="/img/socialmedia/icons/icons_001.png"> <..." Line: 33 Column: 7 - 129
"...k"> <img id="gplus_small" class="socialMediaIconSmall" height="129px" width="174px" src="/img/socialmedia/icons/icons_001.png"> <..." Line: 65 Column: 5 - 69
"...px;"> <img src="/img/brand/openintro_homepage_banner_graphics_20160402.png" height="1260" width="570" style="margin: -105px 0 0 -93px;"> </d..." Line: 78 Column: 5 - 70
"...px;"> <img src="/img/brand/openintro_homepage_banner_graphics_20160402.png" height="1260" width="570" style="margin: -483px 0 0 -170px;"> </d..." Line: 92 Column: 5 - 69
"...px;"> <img src="/img/brand/openintro_homepage_banner_graphics_20160402.png" height="1260" width="570" style="margin: -878px 0 0 -70px;"> </d..." Line: 108 Column: 7 - 45
"...;"> <img class="fpBannerIcon" height="330" width="209" style="margin: -20px 0 0 -145px;" src="/img/subjects/statOverview_001.png"> <..." Line: 123 Column: 4 - 45
"...0px;"> <img class="statPageIcon" height="301" width="190" style="margin: -105px 0 0 0;" src="/img/subjects/statOverview_002.png"> <..."

Bad value “129px” for attribute “height” on element “img”: Expected a digit but saw “p” instead.

Line: 23 Column: 7 - 131
"...k"> <img id="twitter_small" class="socialMediaIconSmall" height="129px" width="174px" src="/img/socialmedia/icons/icons_001.png"> <..." Line: 28 Column: 7 - 131
"...k"> <img id="youtube_small" class="socialMediaIconSmall" height="129px" width="174px" src="/img/socialmedia/icons/icons_001.png"> <..." Line: 33 Column: 7 - 129
"...k"> <img id="gplus_small" class="socialMediaIconSmall" height="129px" width="174px" src="/img/socialmedia/icons/icons_001.png"> <..."

Bad value “174px” for attribute “width” on element “img”: Expected a digit but saw “p” instead.

Duplicate ID “mrights”.

Line: 41 Column: 2 - 60
"...> </li> <li class="mmenu" id="mrights" style="margin-right: 53px;"> <a..." Line: 44 Column: 2 - 60
"...> </li> <li class="mmenu" id="mrights" style="margin-right: 22px;"> <a..." Line: 47 Column: 2 - 59
"...> </li> <li class="mmenu" id="mrights" style="margin-right: 0px;"> <a..."

Attribute “alt” not allowed on element “div” at this point.

Line: 97 Column: 3 - 93
"...ntrol"> <div class="panel_control_dot panel_control_dot_on" id="dot_1" alt="Click to view panel 1"></div>..." Line: 98 Column: 3 - 72
"...></div> <div class="panel_control_dot" id="dot_2" alt="Click to view panel 2"></div>..." Line: 99 Column: 3 - 72
"...></div> <div class="panel_control_dot" id="dot_3" alt="Click to view panel 3"></div>..."

Attribute “alt” not allowed on element “a” at this point.

Line: 164 Column: 4 - 70
"...erms"> <a href="/terms.php" class="mmenu" id="mtermsA" alt="Terms of Use">Terms<..."

Warnings

The first occurrence of ID “mrights” was here.

Line: 38 Column: 2 - 60
"..."mmenu"> <li class="mmenu" id="mrights" style="margin-right: 40px;"> <a..." Line: 38 Column: 2 - 60
"..."mmenu"> <li class="mmenu" id="mrights" style="margin-right: 40px;"> <a..." Line: 38 Column: 2 - 60
"..."mmenu"> <li class="mmenu" id="mrights" style="margin-right: 40px;"> <a..."

Article lacks heading. Consider using “h2”-“h6” elements to add identifying headings to all articles.

Line: 51 Column: 41 - 49
"...enter824"><article> <div ..."

Section lacks heading. Consider using “h2”-“h6” elements to add identifying headings to all sections.

Line: 51 Column: 14 - 40
"...div></nav><section class="center824"><artic..."

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openintro.org Ping

Ping is a computer network administration software utility used to test the reachability of a host on an Internet Protocol (IP) network. It measures the round-trip time for messages sent from the originating host to a destination computer that are echoed back to the source.

openintro.org TRACEROUTE

Traceroute is a computer network diagnostic tool for displaying the route (path) and measuring transit delays of packets across an Internet Protocol (IP) network. The history of the route is recorded as the round-trip times of the packets received from each successive host (remote node) in the route (path); the sum of the mean times in each hop is a measure of the total time spent to establish the connection. Traceroute proceeds unless all (three) sent packets are lost more than twice, then the connection is lost and the route cannot be evaluated.

OPENINTRO.ORG OpenIntro: developer and promoter of educational products that are free, transparent, and lower barriers to education.

openintro.org Website Information

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openintro.org Alexa Rank

openintro.org whois

openintro.org server information

Servers Location

openintro.org desktop page speed rank

openintro.org Desktop Speed Test Quick Summary

priority - 10Eliminate render-blocking JavaScript and CSS in above-the-fold content

Your page has 2 blocking script resources and 2 blocking CSS resources. This causes a delay in rendering your page.

Remove render-blocking JavaScript:

Optimize CSS Delivery of the following:

priority - 9Optimize images

Properly formatting and compressing images can save many bytes of data.

Optimize the following images to reduce their size by 91.7KiB (70% reduction).

priority - 7Leverage browser caching

Setting an expiry date or a maximum age in the HTTP headers for static resources instructs the browser to load previously downloaded resources from local disk rather than over the network.

Leverage browser caching for the following cacheable resources:

priority - 1Reduce server response time

In our test, your server responded in 0.25 seconds.

priority - 0Minify JavaScript

Compacting JavaScript code can save many bytes of data and speed up downloading, parsing, and execution time.

Minify JavaScript for the following resources to reduce their size by 4.7KiB (28% reduction).

priority - 0Minify CSS

Compacting CSS code can save many bytes of data and speed up download and parse times.

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priority - 0Minify HTML

Compacting HTML code, including any inline JavaScript and CSS contained in it, can save many bytes of data and speed up download and parse times.

Minify HTML for the following resources to reduce their size by 399B (13% reduction).

openintro.org Desktop Resource Breakdown

openintro.org mobile page speed rank

openintro.org Mobile Speed Test Quick Summary

priority - 40Eliminate render-blocking JavaScript and CSS in above-the-fold content

Your page has 2 blocking script resources and 2 blocking CSS resources. This causes a delay in rendering your page.

Remove render-blocking JavaScript:

Optimize CSS Delivery of the following:

priority - 11Leverage browser caching

Setting an expiry date or a maximum age in the HTTP headers for static resources instructs the browser to load previously downloaded resources from local disk rather than over the network.

Leverage browser caching for the following cacheable resources:

priority - 3Optimize images

Properly formatting and compressing images can save many bytes of data.

Optimize the following images to reduce their size by 32.5KiB (30% reduction).

priority - 0Minify JavaScript

Compacting JavaScript code can save many bytes of data and speed up downloading, parsing, and execution time.

Minify JavaScript for the following resources to reduce their size by 4.7KiB (28% reduction).

priority - 0Reduce server response time

In our test, your server responded in 0.23 seconds.

priority - 0Minify CSS

Compacting CSS code can save many bytes of data and speed up download and parse times.

Minify CSS for the following resources to reduce their size by 1.9KiB (24% reduction).

priority - 0Minify HTML

Compacting HTML code, including any inline JavaScript and CSS contained in it, can save many bytes of data and speed up download and parse times.

Minify HTML for the following resources to reduce their size by 399B (13% reduction).

openintro.org Mobile Resource Breakdown

openintro.org mobile page usability

openintro.org Mobile Usability Test Quick Summary

priority - 10Configure the viewport

Your page does not have a viewport specified. This causes mobile devices to render your page as it would appear on a desktop browser, scaling it down to fit on a mobile screen. Configure a viewport to allow your page to render properly on all devices.

priority - 6Size tap targets appropriately

Some of the links/buttons on your webpage may be too small for a user to easily tap on a touchscreen. Consider making these tap targets larger to provide a better user experience.

The following tap targets are close to other nearby tap targets and may need additional spacing around them.

priority - 5Use legible font sizes

The following text on your page renders in a way that may be difficult for some of your visitors to read. Use legible font sizes to provide a better user experience.

The following text fragments have a small font size. Increase the font size to make them more legible.

openintro.org HTML validation

Errors

A “meta” element with an “http-equiv” attribute whose value is “X-UA-Compatible” must have a “content” attribute with the value “IE=edge”.

An “img” element must have an “alt” attribute, except under certain conditions. For details, consult guidance on providing text alternatives for images.

Bad value “129px” for attribute “height” on element “img”: Expected a digit but saw “p” instead.

Bad value “174px” for attribute “width” on element “img”: Expected a digit but saw “p” instead.

Duplicate ID “mrights”.

Attribute “alt” not allowed on element “div” at this point.

Attribute “alt” not allowed on element “a” at this point.

Warnings

The first occurrence of ID “mrights” was here.

Article lacks heading. Consider using “h2”-“h6” elements to add identifying headings to all articles.

Section lacks heading. Consider using “h2”-“h6” elements to add identifying headings to all sections.

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