Configuring MathJax v1.1

You have been directed to this site because the page you were viewing uses MathJax without providing an explicit configuration.  In version 1.0 of MathJax, this would cause a default configuration file (config/MathJax.js) to be loaded to configure MathJax.

As of version 1.1, you must configure MathJax either by loading a configuration file explicitly or by including in-line configuration that sets the jax array. MathJax no longer loads a default configuration file. If your page used to use

    <script type="text/javascript" src="/MathJax/MathJax.js"></script>

then you will need to add an explicit reference to load you configuration file. For example,

    <script type="text/javascript" src="/MathJax/MathJax.js?config=default"></script>

will load the file config/default.js to perform the configuration. Because the name config/MathJax.js caused some confusion, it has been renamed config/default.js instead, so you should edit the config/default.js file to correspond to the configuration you want (e.g., that configuration that you had in config/MathJax.js).

More information is available in the Loading and Configuring MathJax documentation, and the Migrating from v1.0 to v1.1 documentation.

  • John Gilmer

    I got an error message about the config file when I was running the statistics course of the Open Learning Initiative sponsored by CMU.

    But all the “configuration” information seems to be aimed at the server which, I think, I don’t have access to.

    What am I missing?


  • Adam Stevens

    Yea what am I supposed to do for a page loaded from a web server??

  • Robert Miner

    If you don’t control the page content that caused the error, you can ignore the warning dialog. The person who does control the page content will have to fix the problem, so if there is a webmaster address or something like that, you could mail them the link to this page, just in case they didn’t realize they have some pages still set up for use with MJ1.0, even though they are using MJ1.1.

  • Japhet

    I don’t know the explicit configuration specification. please help

  • Japhet

    Please what do you mean by explicit configuration specification?

  • uche

    is this config. mandatory?

  • Davide Cervone

    @Japhet: an “explicit configuration” is either the inclusion of ?config=config-file on the script tag that loads MathJax.js, or the inclusion of a script of type text/x-mathjax-config that includes a MathJax.Hub.Config() call that sets the jax array explicitly.

    Prior to MathJax v1.1, MathJax would load a default configuration file if neither of these was present, but as of v1.1, that is no longer the case. The paragraphs above explain this in more detail.

    If you are not the author of the page where you are getting the message about setting the configuration, then there is nothing you need to do. If your network connection is a slow one, it may be that MathJax is timing out while trying to obtain its configuration file, and that could be what is causing this message. Try reloading the page and see if you still get the message.

    MathJax v2.0 will be somewhat more restrictive about putting up this message.

    @uche: Yes, a configuration is mandatory in order for MathJax to function properly. If you are authoring a page that uses MathJax, you will need to use one of the two methods described above to tell MathJax what input and output processors to use. The config= approach using one of the pre-defined configurations is the easiest approach.

  • b cameron

    why is this really necessary, its taking up my rime and running all over my pages

  • Davide Cervone

    When we added the CDN service, that meant that you no longer host MathJax on your own server, and so could not edit the default.js yourself. That meant we needed a new mechanism to allow you to configure MathJax without having edit access to the configuration files. So we provided several pre-defined configurations for different use cases, and we provide in-line configuration in case you need to customize those configurations. Without this, you would not be able to configure MathJax.

    If your page does include config=file and you are still getting this message, that may be because you either have a typo in the configuration file name, or because the configuration file took too long to download and MathJax timed out waiting for it.

    I do not understand what you mean it is running all over your pages. Perhaps if you point us to your page we can help you out.


  • Shobhit Bhatnagar

    I recieved the following error…

    MathJax no longer loads a default configuration file; you must specify such files explicitly. This page seems to use the older default config/MathJax.js file, and so needs to be updated. This is explained further at

  • TonyK

    “If you are not the author of the page where you are getting the message about setting the configuration, then there is nothing you need to do.”

    Surely what you meant so say is, “There is nothing you *can* do.” Right?

  • Davide P. Cervone

    > Surely what you meant so say is, “There is nothing you *can* do.” Right?

    You are right, there is nothing a non-author can do. But the remark was meant to be reassuring for those who get the message but are not the ones who need to see it, so in that sense, telling them they don’t need to do anything is probably better than telling them there is nothing they can do.


  • http://Google Asutosh

    When I open the page for to know about big bang theory suddenly a notice flashes on screen about of mathjax configuration further on I dont understand

  • http://OpenLearningInitiative Rodrigo Salazar

    Is there a simpler way to fix this?

  • Davide P. Cervone

    @rodrigo: I’m not sure what could be simpler than adding ?config=default to the <script> tag that loads MathJax (or one of the predefined configuration files listed in the documentation linked above rather than default). What is it about this that is complicating the issue for you?


  • http://specek18 Dawid

    When I open the page for to know about big bang theory suddenly a notice flashes on screen about of mathjax configuration further on I dont understand

  • Alfredo Louro

    Or I can just uninstall GmailTeX.

  • williams Helen

    I don’t seem to understand what explicit mean, and how to go about updating the file.

  • Peter Krautzberger

    I’m not sure what you’re referring to, but did you see Davide Cervone’s comment above?

    Also, you will reach more people if you ask a question directly on the MathJax User Group.

  • http://Mathjax gail gilbert

    Hi—what happens if I ignore the message that I received when I opened my online information regarding refiguring Mathjax. I don’t understand what this is about, and/or why I might need it. Can you help? Thanks–gail

  • Peter Krautzberger

    I’m not sure what you are referring to. I’m guessing you have been using (or encountering a website using) a beta version of MathJax.

    We will remove the beta versions from the CDN in the near future; older releases will remain available through the CDN. If you switch the MathJax installation to a proper release, the warning will disappear.

  • Davide Cervone

    @gail gilbert: If you are not the author of the page you are looking at, there is nothing you need to do.

  • Read

    Hi, I can not use use any portion of E-Learn without encountering an error message that links me to this page, which offers no solution; Sweet.

  • Peter Krautzberger

    I’m sorry for the inconvenience, but this indicates that MathJax isn’t configured correctly on the page that led you here. Please contact the authors of that site and tell them to look into it; only they can fix their page.

  • Read

    Could this have to do with the fact I am using an Apple computer? I tried the same site from a PC and did not have the same navigation nightmare.

  • Peter Krautzberger

    No, MathJax works the same on all browsers, independent of the operating system.

    You need to contact the support of you elearning site and let them know that they have a configuration problem. We’ll be happy to assist them on the MathJax User Group.

  • pam hosley

    I keep getting this error can you please help?

  • Peter Krautzberger

    If you get the error that MathJax no longer loads a default configuration file on somebody else’s website, the best you can do is tell the website’s administrators that they have configured MathJax incorrectly. As a visitor, there’s nothing else you can do, I’m afraid.

  • Wonney

    Gostaria de saber em português se possível como faço para resolver o problema que estou entrando em um site e ele está colocando isso: MathJax no longer loads a default configuration file; you must specify such files explicitly. This page seems to use the older default config/MathJax.js file, and so needs to be updated. This is explained further at

  • Peter Krautzberger

    Please contact the author of the page you visited — they have to update their configuration.

  • Waldelourdes

    traduzindo: Você foi direcionado para este site, pois a página que você estava vendo usa MathJax sem fornecer uma configuração explícita. Na versão 1.0 do MathJax, isso faria com que um arquivo de configuração padrão (config / MathJax.js) a ser carregado para configurar MathJax.

    A partir da versão 1.1, você deve configurar MathJax ou carregando um arquivo de configuração explícita ou inclusive na linha de configuração que define a matriz jax. MathJax já não carrega um arquivo de configuração padrão. Se a sua página costumava usar

    então você vai precisar adicionar uma referência explícita para carregar você arquivo de configuração. Por exemplo, a

    irá carregar o arquivo de configuração / Default.js para realizar a configuração. Como o nome do config / MathJax.js causou alguma confusão, ele foi renomeado config / Default.js vez, então você deve editar o config / Default.js arquivo para corresponder à configuração que você quer (por exemplo, que a configuração que você tinha em config / MathJax.js).

    Mais informações estão disponíveis na documentação de carga e Configurando MathJax, eo Migrando do v1.0 a documentação v1.1.

  • ir

    Would creating v1.1 to be backwards compatible not have been better, rather than making people re-do their script tags? If no configuration has been defined, load the default, rather than popping up a message?

  • mathjax

    Maybe, but this was a decision reached 18 months ago, after careful consideration about the impact of a number of interacting changes between v1.0 and v1.1.

  • HGM

    Clearly – backwards incompatible changes upset everyone who depends on your work, and should not be made lightly.

  • sumit

    from where and how this script are applicable

  • Grant

    I don’t know how to apply this advice in the case that I’m using the MathJax LaTeX plugin in WordPress. I don’t think I should have to manually add the tag to every page on my site. Should the plugin itself implement the new configuration? Or is there a way I can do it myself, globally?

  • Grant

    Addendum to the above: I found when I deactivate and reactivate the plugin, the problem disappears and everything displays correctly. But after a time (in my case a week or two), it breaks again, and I get the configuration message.

  • mathjax

    Sorry to hear that you’re encountering problems. The plugin might be the problem if it uses an outdated configuration. Unfortunately, we cannot provide support for third party plugins. It’s best to contact the author(s) of the wordpress plugin you’re using.

  • Jim-bo-bob

    So how does this help? I’m just a visitor to said page.

  • mathjax

    We’re afraid there’s not much you can do as a visitor, except contact the page author.

  • Роман