KnolCase is a case-based knowledge management tool for gathering information about subjects of interest and organizing these into case files. This can be used by researchers, investigators, journalists and others to collect, organize, share, and publish facts about topics. It is a personal, distributed knowledge base tool. You can create your own case files with topics like persons, companies, organizations, places, articles, notes, documents, references, etc. Topics are connected through properties, essentially forming a network of linked topics.

The case files are stored locally on your computer giving you a high degree of privacy. You can choose to share your case file so others can view it or you can publish the case topics in the public SLING knowledge base. You can also share your case files privately. Then your data will only be available to other users you have shared the secret key with. The data is end-to-end encrypted and only the encrypted version is stored centrally.

You can choose to export your information to Wikidata to make your contributions available to a broader audience. Then your information will ultimately be available in places like Google search knowledge panels, Siri, as well as many other places.


Table of content

Case files

KnolCase organizes topics and facts around case files. A case file groups topics about a subject into a single document. Case files are stored locally on your own computer in the browser's local database ().

NB: Please notice that if you use KnolCase in , your case file will be deleted by the browser when you close the browser window, so you shouldn't use KnolCase in incognito mode for cases that you want to keep. You should also be careful when clearing cookies and browsing data. It is important NOT to delete the local site data (for Otherwise all your case files will be deleted. There are no backup copies on of your case files, so they will be gone for good. You're advised to back up your case data on a regular basis.

Each case file is assigned a unique case number by a central case numbering service. You can view or edit a case by going to the url for the case, e.g. for case #1234. You can only edit a case if you're the owner of the case. Also, the case can only be viewed by others if it has been shared. By default a case is private, so it cannot be viewed by anyone else.

A case file contains a number of topics grouped into folders. A topic can be in multiple folders. The first topic in the Main folder is the case topic, which is the topic for the case itself. The case topic cannot be deleted. It contains information about the case file like name, description, author, and case number, but you can add any information you like to the main topic, e.g. a with a reference to the central entity of the case.

Opening a new case

Click the add button to open a new case. Type the name of the case you want to research and an optional description. Then click "Create". This opens the new case and you can now start to add topics to the case.

You add new topics to the case by typing the name of the topic in the search bar. If the topic is already in the knowledge base, you can just select it from the search list. This creates a topic that is an extension of an existing topic and you can click expand_more to see the existing information. Otherwise, pressing Enter without selecting a topic will create a new topic.

After you have made changes to the case, you can save it by clicking save or by pressing Ctrl+S. The case file is stored in the local database in your browser.

Managing your case files

The KnolCase home screen ( shows you a list of all your case files on the computer. Case files are local to the computer and user, so you can only see the case files you have created on this computer with this user account. The case list shows the case number, status, name, description, creation date, and last modification date. The most recently modified cases are shown first. You can open a case by clicking on it in the list. You can delete a case by clicking the delete button. Only the local link will be deleted for linked cases and collaborations.

The status icons show the status of each case:

share case that you have shared so anyone with the case number can view it
lock case that you have shared secretly so it can only be viewed by other users with the secret key; only an encrypted copy of the case will be stored on the server
link link to case that someone else has shared
key link with secret key to encrypted case that someone else has shared with you
public case that you have published making all topics in the case available in KnolBase
people link to collaboration case which can be viewed and edited by all participants in the collaboration
* case has been modified since it was last shared
(no icon) private case that is only stored locally and not shared with anyone

Case topics

A topic is similar to a , but is it local to the case file. Topics are used to represent all the things in human knowledge, including concepts, objects, subjects, and entities. If a topic represents a concept or an abstract object, it usually has a property. If the topic represents a concrete object, e.g. a person, it usually has an , property which describes its type. Many common topics will already be in KnolBase and Wikidata, so topics in case files will often be new entities like persons, organization, locations, and documents, but you can make topics for any entities and concepts you're interested in.

Each topic is assigned a unique topic id which contains the case number as well as a serial number within the case, e.g. topic number 10 in case #1234 will be assigned t/1234/10 as its topic id. Topic ids are never reused even if you delete the topic.

A topic usually has a name and a description. Topic names do not have to be unique. The desciption can be used for disambiguating topics with the same name. You can also add one or more aliases for the topic. Theses can be different names the entity is known under, and spelling variations of these.

A topic consists of a number of statements. A statement has a property and a value. You can use all the properties defined by Wikidata, but you can also just use text for properties. The datatype for the property value is determined by the property, but in most cases you can override the predefined datatype, e.g. you can just specify a text value for a reference property. KnolCase supports the following datatypes:

You can qualify a statement with other statement to expand on, annotate, or contextualize beyond what can be expressed in just a simple property-value pair. Qualifiers are used in order to further describe or refine the value of a property given in a statement. A statement should still provide useful data even without a qualifier; the qualifier is just there to provide additional information. Qualifier can modify what a topic means, indicate how the value of a property was determined, constrain the validity of the value, or offer further details that cannot otherwise be expressed using simple property-value pairs. Qualifiers are aldo used for temporal information like for an event, or and to specify the period where the statement applies.

You can make a topic an extension of another topic by adding an "is:" statement to the topic. If you publish the topic, it will be merged with the topic it is extending. This can be used to add additional facts to an already existing topic. If you add multiple "is:" statements to a topic, it will be merged will all the extended topics during reconciliation.

Editing topics

You can edit a topic by clicking the edit button in the topic toolbar or by pressing Enter when the topic is selected. The topic editor works much like a normal text editor where you can use the cursor and editing keys to move around and edit the topic facts. Each line is a statement with a property and a value separated by colon.

You add new statements by starting to type the property name on a blank line. You can add blank lines by pressing Enter. A search box with the matching properties is shown below the statement line. The search list is updated as you type, but you can also use Shift+Space to open and close the search list. Properties are ranked based on how common they are for the topic type ( and ). You can select the property from the search list using the up and down keys or click on the topic in the list. Pressing Tab will select the first match in the list. This adds the property to the statement and moves the cursor to the statement value after the colon. You can repeat the previous property by pressing Tab on a blank line.

There are approximately 5000 properties in Wikidata plus more than 5000 cross reference properties. In addition to this, you can define custom properties, or just use a text string as the property name. However, some properties are more common than others, so you can select these with one-letter shortcuts:

Many topics are persons (aka in Wikidata lingo). Some common properties for persons are:

You can use Ctrl+M (male) and Ctrl+F (female) as shortcuts to add : and : or to the topic.

Pressing Space at the beginning of the line make the statement a qualifier of the previous statement. A qualified statement can be unqualified by pressing Backspace at the beginning of the line.

Statement values are entered much in the same way as properties, but it searches for matching values in more places:

The search ranking is based on overall item popularity as welll as how common the item type is for the property. If you you do no select a value from the search list, the statement value will just be a text. You can add unstructured notes to the topic by adding comments. Comments are displayed with a bullet (⚫︎) in front, and they are not published in the knowledge base.

You can select one or more statements, by selecting them with the mouse, or by holding down Shift when moving around with the arrow keys, just like you would do in any other text editor. Statements can be copied to the clipboard with Ctrl+C or cut with Ctrl+X. When you copy a statement (i.e. a property with a value), the resolved property and topic ids are preserved, so when you paste them back into the same topic or another topic, they will refer to the same property and topic ids as the place you copied them from.

When you're done editing the topic, you can save the changes by clicking save_alt or by pressing Ctrl+S. If you regret the changes to the topic, you can discard them by clicking cancel or pressing Esc.

Copying and moving topics

You can cut, copy, and paste topics. Ctrl+C copies the selected topic(s) to the clipboard. You select a topic by clicking on the background of the topic card. A topic has a blue border when it is selected.

You can select multiple topics by selecting the first one and then then holding down the Shift key when selecting the last topic. You can also use the up and down keys to change the selection. Holding down the Shift key will extend or shrink the selection. Ctrl+A selects all topics in the current folder. The topic(s) will be stored in SLING text format in the clipboard.

Topics in the clipboard can be inserted into the current folder with Ctrl+V. This inserts the topic(s) right after the (first) selected topic or at the end if no topics are selected.

A topic can be in multiple folders at the same time. When topics are copied and pasted within the same case file, it just adds references to the existing underlying topics in the case. If a topic is edited in one folder, the changes will be shown in the other folders with a reference to the topic.

Topics can also be copied between cases. This will assign new topic ids to the pasted topics but it preserves the internal links between the topics.

You can move topics by cutting them to the clipboard with Ctrl+X. This will delete the topics from the current folder and add them to the scraps folder. You can then go to another folder and paste the topics into this. This will move the topics from the scraps folder to the new folder. The scrap folder is emptied when you save the case (Ctrl+S) or select "Clear" from the scraps folder context menu.

Ctrl+D copies the id of the selected topic to the clipboard and Ctrl+E copies the topic name to the clipboard. You can copy all the topics in the case file to the clipboard by selecting "Copy all" in the KnolCase menu in the top right-hand corner.

Case folders

Topics are organized into folders. The folder list is to the left of the topic panel and you can open and close it by clicking the menu icon in the upper-left corner. The current folder is shown in bold and you can switch to another folder by clicking it in the folder list.

You can add new folders by clicking create_new_folder above the folder list. Each folder has a context menu (more_vert) with functions for renaming the folder, moving the folder up and down in the list, and for deleting the folder. A folder can only be deleted if it is empty.

Case sharing

Your case files are stored locally on your own computer so no one else can view them. If you want to share your case file with others, you can click on the share button in the toolbar. Then you can choose between the following levels of sharing:


You can use case sharing to let other users view your cases, but they cannot make changes to them. If you want to work together with other users on a case, you can turn your case file into a collaboration. This will store the case file on a collaboration server. Then all participants in the collaboration can view and change the case file simultaneously. When a participant makes changes to the case, they will be propagated and displayed immediately to all other connected participants (like Google Docs).

Before you can collaborate on a case, you need to set yourself as the author of the case by adding an statement to the main case topic. You can use your id from KnolCase or Wikidata, but if you are not in the knowledge base, you can add a topic to the case for yourself. Alternatively, you can make a biography case for yourself with your CV and publish this case. You can then set your topic id (Ctrl+D) from this case as the default author for new cases in the general settings (settings).

You can turn a local case into a collaboration by selecting 'Collaborate' in the case toolbar menu. You can then provide the URL for the collaboration server or use the default (wss:// and then click "Collaborate". This moves the case from your own computer to the collaboration server and creates your credentials for accessing the collaboration.

After you have created the collaboration, you can start to invite other participants, by clicking the people button in the case toolbar. You can search for the new participant or add a new participant to the collaboration case itself. This adds the new participant to the main case topic and copies the invite URL to the clipboard. You can then use any (secure) communication medium to send the URL to the participant.

When the new participant clicks the URL, the collaboration server will check if the invite is valid. Please notice that invite URLs expires each time the collaboration server is restarted. This means that invites to the default collaboration server must be activated before the next day. If the invite is valid, credentials for the participant are created and stored on their local computer. Next time they want to access the collaboration, they can just click on the collaboration case in the case list, and a connection to the collaboration server will be established using the stored credentials.

Importing and exporting data

You can import data from local files on your computer into a case by selecting "Import from file" in KnolCase menu (more_vert). Choose the file format in the file dialog and then select the file to import. The following file format are supported:

Wikidata export

You can export case topics to Wikidata by selecting the topic(s) and clicking the Wikidata button in the KnolCase toolbar. The first time you do this, you are asked to authorize SLING to make changes to Wikidata on your behalf. For existing topics, which already have a Wikidata QID, the item will be updated with new facts from the topic. Otherwise, new Wikidata items will be created, and the new QID will be added to the topic. Exporting to Wikidata will never overwrite or delete any existing information in Wikidata.

Not all facts from topics can be exported to Wikidata. Statements which use non-Wikidata properties or values will be skipped. Wikidata is also more strict in terms of data types for properties, so statements where the data value type does not match the property type will also be skipped.

Upload files

You can upload files from you computer to a case using the "Upload files" command in the KnolCase menu (more_vert). This uploads the selected files to the SLING drive server (, and adds a document topic to the case for each uploaded file with information about the filename, date, size, URL, and file type.

The uploaded files can be accessed by anyone with the URL, but the URLs contain a 64-bit crypto random key that makes it virtually impossible to guess the URL, so in reality you need access to the case in order to view the uploaded files. This should be good enough in most cases, but you should not use it to store state secrets.

Backup and restore

Your case files are stored in the browser's local database. You can make a backup of all these by selecting "Backup" in the case manager menu (more_vert). This saves all the cases to a file that you can store in a safe place for disaster recovery. You can also use this to move your case files to another computer.

The backup can be restored by clicking "Restore" in the case manager menu (more_vert) and selecting the backup file. This reads the backed up cases into your browser's local database. This can be used to restore your case files if you have accidentally deleted them, e.g. by clearing your cookies and local data. You should be careful with having the same case files on multiple computers at the same time as this can lead to conflicting updates. You can use collaborations for cases that you need to access from more than one computer.


KnolCase has a number of plug-ins that can be activated by pasting URLs into the search box or a topic, letting you import information from other sites or applications in a quick and easy manner. Plug-ins are loaded on-the-fly when you paste a URL that matches the plug-in URL pattern into the search box or a topic. If you paste a URL into the search box, you can select the plug-in in the search results. This will add a new topic produced by the plug-on to the current folder. Pasting a URL matching a plug-in into a topic will add the retrieved information from the plug-in to the selected topic. External references are checked against the cross-reference register in KnolBase and the topic is extended with any matches found.


"" it is said. You can add pictures to a topic by selecting a topic and pasting an image URL into it (i.e. a URL ending with .jpg, .jpeg, .gif, .png, .mp4, .webm, .webp, or .avif). This adds the picture to the photo gallery of the topic. You can browse the photo gallery by clicking on the photo to the right in the topic card. To get the URL for a picture on any webpage, right-click on the image and select "Copy image address" in the context menu (Chrome).

Pictures on the internet often disappear after a short time. To prevent the pictures in your case topics from disappearing, you can cache the images on the SLING media cache service by selecting "Cache images" in the KnolCase menu (more_vert) in the top right-hand corner. Then all the images in the case file will be cached in the background and you will still be able to view them after they have disappeared from their original location.

Some sites do not allow which prevents images from these sites from being displayed properly in KnolCase. In this case, you can paste the image into the topic instead of just the image URL. You can copy an image by right-clicking on an image on a webpage and selecting "Copy image" in the context menu (Chrome). When you paste an image into a topic, it will first be stored on using a randomized URL, and then this image is added to the topic.

You can also paste gallery URLs into a topic. A gallery URL starts with "gallery:" followed by a list of image URLs separated by space. This format is supported by the Reddit photo search tool. Albums from Reddit and Imgur are also supported. You can search for images for a topic by clicking the image_search button on the topic toolbar.


Pasting a URL from an article or webpage into the search box will create a new topic for this page. You can also select a topic and paste the URL to add information to an existing topic. This is useful for keeping references to webpages and articles where you have found information about a topic.

KnolCase uses the meta tags from the webpage to create a topic with information about the page. It supports Facebook OpenGraph, Twitter Cards, JSON-LD, Dublin Core, Sailthru, as well as a number of generic meta tags:

KnolCase has a database of more than 3000 news sites with their Wikidata QIDs to identify the publisher of a webpage.

For example, if you want to document the source for some fact in a topic, you can add a qualifier with the source:

  1. Press Enter to make room for a new statement
  2. Press Space on the new line to start a qualifier
  3. Type 'source' and then Tab to add a property
  4. Paste the URL for the source and press Tab.

This will create a new topic for the web article with meta data and add this as the source.

Data tables

You can import tables from spreadsheets by copying some rows and columns into the clipboard and pasting these into a folder in KnolCase. You can copy data from any source that supports comma-separated or tab-separated values (CVS/TSV format).

The first row should contain the property/column names. These can be property ids (PIDs) or property names.

Each of the remaining rows are imported as a new topic. If a column name ends with #, e.g. ID#, it is expected to contain item or topic ids. Otherwise, the value is parsed according to the data type of the property, e.g. dates, number, URLs, quantities, etc.

Site plug-ins

KnolCase also has more specialized plug-ins that can import data from specific sites:

These plug-ins let you add a lot of information to topics by just copy and pasting URLs. For example, you can make a web search for a topic by clicking the search button in the topic toolbar to find the sites with information about the topic. You can copy the URL for the webpage using Ctrl+L Ctrl+C. Sometimes you might not even need to visit the webpage. You can copy the result URL by left-clicking on the blue link and selecting "Copy link address".

External references

You can paste URLs from many other sites with information about the topic. This adds an external references of the appropriate type to the selected topic. The following sites are supported:

Please contact us if you have other sites with Wikidata reference properties that you want to use. If the property has a this is usually easy to accomplish.