Title: Link Checker Professional
Author: Marco Beierer
Published: <strong>10 augustus 2015</strong>
Last modified: 14 januari 2023

---

Plugins zoeken

![](https://ps.w.org/link-checker/assets/banner-772x250.png?rev=1217503)

Deze plugin **is niet getest met de laatste 3 grotere versies van WordPress**. Mogelijk
wordt het niet meer onderhouden of ondersteund. Ook kunnen er compatibiliteitsproblemen
ontstaan wanneer het wordt gebruikt met recentere versies van WordPress.

![](https://ps.w.org/link-checker/assets/icon-128x128.png?rev=1217503)

# Link Checker Professional

 Door [Marco Beierer](https://profiles.wordpress.org/mbsec/)

[Download](https://downloads.wordpress.org/plugin/link-checker.1.18.7.zip)

 * [Details](https://nl.wordpress.org/plugins/link-checker/#description)
 * [Beoordelingen](https://nl.wordpress.org/plugins/link-checker/#reviews)
 *  [Installatie](https://nl.wordpress.org/plugins/link-checker/#installation)
 * [Ontwikkeling](https://nl.wordpress.org/plugins/link-checker/#developers)

 [Ondersteuning](https://wordpress.org/support/plugin/link-checker/)

## Beschrijving

The [Link Checker](https://www.marcobeierer.com/wordpress-plugins/link-checker) 
for WordPress uses an external service to crawl your website and find broken links
and images on your website.

In contrast to search engine tools like the Google Search Console, which only show
if a URL on your website is not reachable, it does not matter for the Link Checker
if the links leads to an internal or external URL. The Link Checker will find all
dead links.

The Link Checker works for every plugin out of the box. The computation costs for
your website is also very low because the crawler does the heavy work and just acts
like a normal visitor, who visits all pages of you website once.

#### Out of service

It’s no longer possible to purchase tokens for the Link Checker as of mid-January
2023.

The service is still available for all users that have already purchased a token
and will be shutdown when the last issued token expires mid-January 2024.

#### Paid plugin

Please note that the Link Checker requires a paid token to operate. The free version
is no longer offered.

#### Videos

You can find videos about the Link Checker on the [Link Checker for WordPress playlist on YouTube](https://www.youtube.com/watch?v=8rUFDp09tjs&list=PL5VYcNma6nfxIrlbpz0f1avXT_JIrUZA1).

#### Mogelijkheden

 * **Simple setup**.
 * **Works out of the box** with all WordPress plugins.
 * **Low computation costs** for your webserver.
 * Lists all broken links and redirects on your website.
 * Support for Polylang (probably also WPML) sites.

#### Technical Features

 * Respects your robots.txt file (also the crawl-delay directive).
    - You can use the user-agents MB-LinkChecker to control the crawler.

#### Additional Features of the Professional Version

 * Check if embedded internal and external **images** are broken.
 * Check if embedded **YouTube videos** are broken.
 * Scheduler to **automatically check a website** once a day and get a summary report
   by email.
 * The result can be exported as CSV file.
 * Form login support to check protected pages like membership areas.
 * The result is saved on the Link Checker server so that it can be fetched multiple
   times without requiring a recheck. For example from different users or with different
   browsers.

#### Upcoming Features

 * Support for checking the availability of videos, CSS files and JS files.

#### Technical Requirements

 * Works with **PHP 5.6 and 7**.

#### Is the service free of charge?

The Link Checker Professional is a paid plugin. A free version was offered for many
years, but since August 2022 only a paid version is available.

[Link Checker Professional](https://www.marcobeierer.com/wordpress-plugins/link-checker-professional)

#### Use of an External Server

The Link Checker uses an external server, operated by the developer of the plugin,
to crawl your website and detect broken links. This means, that there is some communication
between your website and the server. The only data that is communicated to the external
server by your website is the URL of your website and the fact that you are using
WordPress. The server than crawlers your website (as a normal visitor does) and 
answers with a list of the found broken links.

## Schermafbeeldingen

 * [[
 * List of broken links found by the Link Checker.
 * [[
 * Stats of the Link Checker after a check has finished.

## Installatie

 1. Upload the ‘link-checker’ folder to the ‘/wp-content/plugins/’ directory.
 2. De plugin activeren via het ‘Plugin’ menu in WordPress.
 3. Access the generator with the “Link Checker” button in the sidebar and use the “
    Check your website” button to start the process.
 4. The found broken links will be reported to you when the crawler has finished.

## FAQ

### Why could the Link Checker not access my site?

A reason if the Link Checker could not access your site could be that the crawler
of the Link Checker is blocked by your hosting provider. I have observed this issue
especially with free and really cheap hosting providers. Some block crawlers (and
regular visitors) already after five fast sequential requests. The issue could be
fixed by whitelisting the IP of the crawler. However, I think this option is not
available for the affected hosting services. Alternatively it is possible to use
the crawl-delay directive in your robots.txt to set the delay between two requests.

### Which user-agent should I use in the robots.txt file?

The Link Checker uses a custom user-agent group named MB-SiteCrawler. This allows
you a fine grained control of which pages are checked. If you do not define a group
for the custom user-agent in your robots.txt file, the default set in the * group
apply.

### Does the Link Checker work in my local development environment?

No, the Link Checker needs to crawl your website and the generator has no access
to you local network.

### The Link Checker is very slow. What can I do?

In the most cases this is due to the fact that you have set a large value for the
crawl-delay directive in your robots.txt file. Some hosters also add the crawl-delay
directive automatically to your robots.txt file. The crawl-delay defines the time
in seconds between to requests of the crawler.

## Beoordelingen

![](https://secure.gravatar.com/avatar/191205eced5f31b961f30b0de26ce2f8a15e468a7128675653a8299fc944a689?
s=60&d=retro&r=g)

### 󠀁[useless](https://wordpress.org/support/topic/useless-536/)󠁿

 [KJA4U](https://profiles.wordpress.org/kja4u/) 30 juni 2023

The free version is useless.

![](https://secure.gravatar.com/avatar/7855b1802efaac70def792f4b01f82c24b989fcb3f98690b0f13d95cd7010447?
s=60&d=retro&r=g)

### 󠀁[The URL limit was reached. The Link Checker has not checked your whole website.](https://wordpress.org/support/topic/the-url-limit-was-reached-the-link-checker-has-not-checked-your-whole-website/)󠁿

 [cacabe](https://profiles.wordpress.org/cacabe/) 17 februari 2022

The URL limit was reached. The Link Checker has not checked your whole website. 
You can buy a token for the Link Checker Professional to check up to 500’000 URLs.
Thank you for wasting my time !

![](https://secure.gravatar.com/avatar/264fcf0eb542ecefac75924e429f05ea3bc4537d201e025123e9c7a6b4429f45?
s=60&d=retro&r=g)

### 󠀁[500 links limit](https://wordpress.org/support/topic/500-links-limit/)󠁿

 [serdasteclas](https://profiles.wordpress.org/serdasteclas/) 18 oktober 2021

the 500 links limit is too little for any website.

![](https://secure.gravatar.com/avatar/27445269b9132ee5ba8e69d90506b950aa10ca65bea66a402341f43850bc29ec?
s=60&d=retro&r=g)

### 󠀁[Bait and Switch – Pretty much forced to buy if you want to use.](https://wordpress.org/support/topic/remove-this-plugin-for-sketchy-business-practice/)󠁿

 [Chris LOW](https://profiles.wordpress.org/laughter-on-water/) 11 maart 2021 5 
reacties

EDITED REVIEW: 2021.03.10 The free plugin works, but stops before it can finish 
being useful. 500 links is simply not enough for a free version. It doesn’t provide
a free tier that’s functional for most medium-sized websites. You end up having 
to buy it to actually use it. That makes this more of an advertisement than an actual
plugin. I’m using a different plugin. EDITED 2021.03.11 See my reply dated today.
EDIT: The free plugin only checks 500 links. This is entirely useless, even for 
medium-sized sites. EDIT: Plugin registration consists of link allotments, with 
the minimum being 25K links checked in one go for ~50 Euros. It goes up drastically
from there because Marco’s server is the one doing the crawling. Most target websites
are small, hosted on huge commercial properties optimized for WordPress. Additionally,
crawling the local site may not be as optimal as scraping each post’s content field
for links and storing results locally. My server should be the one doing the work.
If my server is doing the work, you can’t expect me to pay by the link for a service
my server is doing. Period. An example of a per unit subscription model that works
is Mailchimp. Their servers are doing the work in a trusted secure environment so
that my web host box doesn’t become a shadow spambot. Offloading that service to
mailchimp is not sketchy, and their terms are more than generous for small to mid-
sized website admins, with a free tier that is actually commodious. That’s not what’s
happening with this plugin. It checks every link on every page, even footer links
that repeat across the entire site, so if you have a link like “theme created by…”,
that link counts on every page against your priced link count. Absurd. Worse, it
counts a number of known valid links as broken. WordPress plugins in the .org library
should offer a reasonable modicum of usefulness out of the gate. It should not seem
hampered to the site admin. The pro version should offer additional capabilities
that make the free plugin seem more complete. This plugin offers only a glimpse 
of what the paid plugin might do if you are willing to pay 45 euros minimum to check
25K links. You want to check more links? Buy more tokens. EDIT: Given the Author’s(
Marco Beierer) balanced response, I’ll say this would better serve the WP community
and Marco himself by: scraping post content directly for links rather than crawling,
removing the tier caps — including for the free version — and then Price the pro
version between $50 and $100 for a single-tier paid version that also includes image
and youtube link checking. Also for the pro version, add the ability to check all
site menu links, sidebar/footer/widget links, post content for custom post-type 
links, custom field links, etc. This would give the expected additional capability
along with unrestricted link checking found in the free version. A great plugin 
makes the free-plugin adopter feel like they’re getting such a bargain they feel
guilty for not supporting the plugin with either a donation or an upgrade to the
pro version.

![](https://secure.gravatar.com/avatar/3b189f07a0bb367cfb92815fb2a349c8914723715332692ff4ed8aaf823f54f6?
s=60&d=retro&r=g)

### 󠀁[Great plugin](https://wordpress.org/support/topic/great-plugin-29049/)󠁿

 [ekofan](https://profiles.wordpress.org/ekofan/) 20 december 2020

Excellent Links plugin for checking and repairing. It helps me a lot. Added new 
features in recent months. Better than others, I recommend it.

![](https://secure.gravatar.com/avatar/aa57c1063bc6e41f1e70fbfe3f230ec7b3539fb459cfc8544cb121b028a44494?
s=60&d=retro&r=g)

### 󠀁[Just 500 link and expensive](https://wordpress.org/support/topic/just-500-link-and-expensive/)󠁿

 [cleciomayrink](https://profiles.wordpress.org/cleciomayrink/) 26 mei 2020

Verify just 500 link and very expensive the professional version.

 [ Lees alle 31 beoordelingen ](https://wordpress.org/support/plugin/link-checker/reviews/)

## Bijdragers & ontwikkelaars

“Link Checker Professional” is open source software. De volgende personen hebben
bijgedragen aan deze plugin.

Bijdragers

 *   [ Marco Beierer ](https://profiles.wordpress.org/mbsec/)

[Vertaal “Link Checker Professional” in je eigen taal.](https://translate.wordpress.org/projects/wp-plugins/link-checker)

### Interesse in ontwikkeling?

[Bekijk de code](https://plugins.trac.wordpress.org/browser/link-checker/), haal
de [SVN repository](https://plugins.svn.wordpress.org/link-checker/) op, of abonneer
je op het [ontwikkellog](https://plugins.trac.wordpress.org/log/link-checker/) via
[RSS](https://plugins.trac.wordpress.org/log/link-checker/?limit=100&mode=stop_on_copy&format=rss).

## Changelog

#### 1.18.7

_Release Date – 14th January, 2023_

 * Out of service info.

#### 1.18.6

_Release Date – 24th October, 2022_

 * Added paywall.

#### 1.18.5

_Release Date – 1st August, 2022_

 * Changed name.

#### 1.18.4

_Release Date – 1st August, 2022_

 * Updated readme.

#### 1.18.3

_Release Date – 1st August, 2022_

 * Added paid version info.
 * Updated ‘Tested up to’ information.

#### 1.18.2

_Release Date – 2nd August, 2021_

 * Updated ‘Tested up to’ information.

#### 1.18.1

_Release Date – 19st October, 2020_

 * Updated ‘Tested up to’ information.

#### 1.18.0

_Release Date – 30st June, 2019_

 * Added selectable interval (daily, weekly, bi-weekly, every 30 days) to scheduler.
 * Added _Mark all with same status code and domain as working_ function.
 * Improved documentation/glossary.

#### 1.17.0

_Release Date – 22st March, 2019_

 * Added form login support.
 * Fixed a security vulnerability (XSS).

#### 1.16.2

_Release Date – 1st March, 2019_

 * Updated ‘Tested up to’ information.

#### 1.16.1

_Release Date – 20th December, 2018_

 * Bugfix for broken CSV download in Firefox.

#### 1.16.0

_Release Date – 21th September, 2018_

 * Show edit link for URLs that could be assigned to a post.
 * Improved status codes page.
 * Improved professional version page.
 * Bugfix: Reset retries count before every check.
 * Crawler: Performance optimizations and some bug fixes.

#### 1.15.1

_Release Date – 21th July, 2018_

 * Force CSS reload because an old version is cached for users of older versions.

#### 1.15.0

_Release Date – 21th July, 2018_

 * Export result as CSV file for users of the professional version.
 * Result is saved on server for customers of the professional version. So the same
   result can be downloaded by multiple users or with multiple browsers.
 * Added hint how to change scheduler email address.

#### 1.14.0

_Release Date – 15th July, 2018_

 * Added message with recommendations for Wordfence users.
 * Result from cache is loaded even if a check is currently running.
 * Old result is not cleared anymore when a new check is started, but just when 
   the new check has finished.
 * Split up the ‘Progress and Stats’ tab in two separate tabs.
 * Added status code and response text to error message.
 * Bugfix: Handle failed IsRunning request.

#### 1.13.0

_Release Date – 12th May, 2018_

 * Added a feedback form.

#### 1.12.1

_Release Date – 8th May, 2018_

 * Bugfix: Start button was not shown in some cases.

#### 1.12.0

_Release Date – 8th May, 2018_

 * New ‘Mark as fixed on all pages’ button.
 * Added Polylang integration.
    - Probably also works with WPML.
 * Compression of results before they get stored in browser cache.
 * Moved scheduler to tab in main view.

#### 1.11.0

_Release Date – 22th April, 2018_

 * Redesigned user interface.
    - Pagination.
    - All-in-one (links, images, videos, working redirects, unhandled resources)
      result view.
 * Performance of user interface was improved so that it’s now possible to view 
   result tables with more than 100’000 broken links or redirects.
 * Use IndexedDB instead of localStorage to store result so that the result set 
   size is not limited to about 5 MB anymore.

#### 1.10.0

_Release Date – 19th April, 2018_

 * Auto-resume support if the Link Checker gets opened and a check is already running
   on the server.
 * Implemented a warning for high crawl-delays.
 * Added a stop button to stop the current check.
 * Implemented protection for check hijacking if token is used.

#### 1.9.1

_Release Date – 17th April, 2018_

 * Fixed redirect stats.

#### 1.9.0

_Release Date – 17th April, 2018_

 * Highlighting of redirects.
 * Added option to show working redirects.
    - Has to be enabled in the settings.
 * Fixed a conflict of the settings page with the settings page of the _Broken Link
   Checker_ plugin.

#### 1.8.0

_Release Date – 9th April, 2018_

 * Results are saved now and don’t get discarded when leaving the Link Checker anymore.
 * Improved navigation with tabs.
 * More detailed stats.
 * Crawler
    - Added status code 603 (Unknown authority error) with explanation.
    - Added cookie support.

#### 1.7.0

_Release Date – 4th March, 2018_

 * Added support for broken embedded YouTube videos.
 * Remove all whitespace (line breaks, spaces, tabs) from token. This prevents Copy
   and Paste issues.
 * Improvement notification message for daily checks.
 * Crawler performance improvements.

#### 1.6.0

_Release Date – 1st March, 2018_

 * Added info box to scheduler and hide register form if no token is present.
 * Hide broken images string and show info that not available.
 * Implemented three retries if request could not be sent or no response was received.
 * Explain changed status codes (598 is now 601 and 599 is 602).
 * Added unhandled resources and images.
 * Crawler
    - Implemented better blocked by robots detection and handling (for external 
      links).

#### 1.5.1

_Release Date – 26th February, 2018_

 * Release 1.5.0 missed some files.

#### 1.5.0

_Release Date – 26th February, 2018_

 * Requires WordPress 4.5
 * Fixed broken links could be removed from the results table with the _Mark as 
   fixed_ button.
 * Added section for links blocked by robots.txt and a _Mark as working_ button 
   to mark them as working after a manual check.
 * Added common status code information.
 * Broken links in the result table are linked now for the case that someone likes
   to verify that a link is really broken.
 * Set default concurrent connections to three.
 * Improved user interface.

#### 1.4.1

_Release Date – 11th February, 2018_

 * Improvements to the crawler.
 * Updated compatibility information (tested up to WordPress 4.9).
 * Bugfixes
    - Fixed returned status code of failing proxy requests.
    - fixed call to wp_die()

#### 1.4.0

_Release Date – 14th September, 2016_

 * Added news subpage.
 * Added custom status codes documentation.

#### 1.3.0

_Release Date – 12th July, 2016_

 * Added an option to define the maximum number of concurrent connections.
 * Better handling of requests to servers that do not response to HEAD requests 
   correctly. This prevents some false positives.
 * Bugfixes
    - Implemented Cache-Control for AJAX requests.
    - Fixed the PHP short tag issue.

#### 1.2.1

_Release Date – 1st February, 2016_

 * Bugfix: Replaced get_site_url() with get_home_url(), which referes to the option“
   Site Address (URL)”.

#### 1.2.0

_Release Date – 23th December, 2015_

 * Implemented a scheduler to automatically check a website once a day.
 * Improved cURL error messages.

#### 1.1.3

_Release Date – 11th November, 2015_

 * Implemented error message if backend is down.
 * Implemented better error messages to detect problems on startup.

#### 1.1.2

_Release Date – 20th October, 2015_

 * Show sales message in status message only if basic version is used.
 * Fixed file_get_contents bug.

#### 1.1.1

_Release Date – 4th October, 2015_

 * Bug fix release.

#### 1.1.0

_Release Date – 4th October, 2015_

 * Added support for check of embedded image.
 * Some improvements and bug fixes in the backend service.
 * Implemented a simple template engine.
 * Implemented 15 seconds timeout for connection establishment.

#### 1.0.4

_Release Date – 27th September, 2015_

 * Another bug fix release for an issue with PHP 5.3.

#### 1.0.3

_Release Date – 27th September, 2015_

 * Load shared_functions.php only if needed.

#### 1.0.2

_Release Date – 27th September, 2015_

 * Bug fix release, one file was missing in the previous release.

#### 1.0.1

_Release Date – 27th September, 2015_

 * Added a check for the correct cURL version.
 * Added a check if the plugin is used in a local development environment.

#### 1.0.0

_Release Date – 20th September, 2015_

 * Do only transfer the results once at the end of the scan and not at each status
   update request.
    - The status update interval was due to this change reduced to one second again.
 * Better interface messages for use with updated API.
 * Display number of already checked links.
 * Check if the backend service is up and running at the start of a link check.

#### 1.0.0-rc.1

_Release Date – 17th September, 2015_

 * Implemented token support for the Link Checker Professional.
 * Reset list of broken links directly and not at the first find if a second check
   is executed.
 * Undone change introduced in 1.0.0-beta.3: Pages blocked by the robots.txt file
   are not parsed from now on as in versions older than 1.0.0-beta.3. I rethought
   this point and think crawlers should respect the robots.txt, no matter which 
   purpose the crawler has.
 * Support for custom user-agent group (MB-SiteCrawler) in robots.txt.
 * Better error reporting if website is not reachable.
 * Reset limit reached message before each run.
 * A status update is now requested every 2.5 seconds instead of every second.

#### 1.0.0-beta.3

_Release Date – 21th August, 2015_

_Please note that the plugin was not changed, just the backend service._

 * The Link Checker is now able to detect the same dead link on multiple pages. 
   Until now the Link Checker only showed the first page where the dead link was
   found.
 * Pages, blocked by the robots.txt file, were not parsed in earlier version. This
   is fixed now.
 * Fixed an issue with the evaluation of the HTML base tag. A base tag href value
   with a trailing slash was not evaluated correctly before.
 * Implemented a timeout on the connection. URLs which time out are shown with an
   error 500 in the Link Checker.
 * Some smaller bug fixes and performance improvements.

#### 1.0.0-beta.2

_Release Date – 14th August, 2015_

 * Changed menu position to a more unique one.

#### 1.0.0-beta.1

_Release Date – 8th August, 2015_

 * Initiële versie.

## Meta

 *  Versie **1.18.7**
 *  Laatst geüpdatet **3 jaar geleden**
 *  Actieve installaties **4.000+**
 *  WordPress versie ** 4.5 of nieuwer **
 *  Getest t/m **6.0.11**
 *  Taal
 * [English (US)](https://wordpress.org/plugins/link-checker/)
 * Tags
 * [Broken Link Checker](https://nl.wordpress.org/plugins/tags/broken-link-checker/)
   [link checker](https://nl.wordpress.org/plugins/tags/link-checker/)[links](https://nl.wordpress.org/plugins/tags/links/)
   [maintenance](https://nl.wordpress.org/plugins/tags/maintenance/)[seo](https://nl.wordpress.org/plugins/tags/seo/)
 *  [Geavanceerde weergave](https://nl.wordpress.org/plugins/link-checker/advanced/)

## Waarderingen

 3.2 van 5 sterren.

 *  [  13 5 sterren beoordelingen     ](https://wordpress.org/support/plugin/link-checker/reviews/?filter=5)
 *  [  2 4 sterren beoordelingen     ](https://wordpress.org/support/plugin/link-checker/reviews/?filter=4)
 *  [  3 3 sterren beoordelingen     ](https://wordpress.org/support/plugin/link-checker/reviews/?filter=3)
 *  [  1 2 ster beoordeling     ](https://wordpress.org/support/plugin/link-checker/reviews/?filter=2)
 *  [  11 1 sterren beoordelingen     ](https://wordpress.org/support/plugin/link-checker/reviews/?filter=1)

[Mijn beoordeling toevoegen](https://wordpress.org/support/plugin/link-checker/reviews/#new-post)

[Bekijk alle beoordelingen](https://wordpress.org/support/plugin/link-checker/reviews/)

## Bijdragers

 *   [ Marco Beierer ](https://profiles.wordpress.org/mbsec/)

## Ondersteuning

Iets te melden? Hulp nodig?

 [Het supportforum bekijken](https://wordpress.org/support/plugin/link-checker/)