Making a reference
Pick what you are citing and the style your teacher or journal asks for, then fill in what you know. The reference is written below as you type, and anything a style needs that is still empty is listed under it. You can switch styles at any time without typing anything again. For a source with no person named as its author, such as a page by a charity or a video on a company's channel, turn on An organisation is the author.
How each style lists authors
APA 7 gives the last name and initials (Levitt, S. D.), joins the last two with an ampersand, and lists up to 20 authors; past that it gives the first 19, an ellipsis, then the last. MLA 9 writes the first author last name first, gives the second in full after and, and shortens three or more to the first author and et al. Chicago lists up to ten authors and, past ten, the first seven and et al. Harvard uses last names and initials joined by and. A source with no author starts with its title instead.
Titles, italics and copying
Titles are kept exactly as you type them. APA asks for sentence case on the titles of books, articles and pages (only the first word, the first word after a colon, and names take a capital), while MLA and Chicago use title case, so change the capitals yourself if your title came from somewhere written in the other way. The parts each style puts in italics, such as a book or journal title, are set in italics here, and Copy carries them over: paste into Word, Google Docs or Pages and the italics come too. Somewhere that only takes plain text gets the same reference without them.
Building a reference list
Add to list moves the reference into the list under the form and empties the form for the next source. The list is kept in alphabetical order, as all four styles ask, and is redrawn in whichever style you pick, so a list started in APA can be switched to MLA in one click. Copy all copies it, one reference per line. Most styles want the list double-spaced with a hanging indent, which you set in your word processor. The list lasts until you close the page; nothing is saved.
Dates, DOIs and access dates
Give as much of the date as the source shows: a year for a book, a month too for a journal if it has one, and the full date for a page or a video. A DOI is the permanent link printed on most journal articles; when you give one it is written as a https://doi.org/ link and used in place of the URL. The Accessed date, when you looked at a web page, is used by MLA, Chicago (when the page has no date) and Harvard. APA leaves it out for pages that do not change.
Questions
Can it fill in the details from a URL or DOI?
No. This page never contacts any other server, so it cannot look a source up. Copy the author, title and date from the page or the book itself; for a journal article, they are usually at the top of the first page.
Which version of each style is this?
APA 7th edition, MLA 9th edition, the bibliography entry of Chicago's notes and bibliography system, and Harvard as most UK universities teach it, following Cite Them Right. Harvard varies a little between universities, so check your own guide for small things like where the full stops go. Each style has a page of its own with its rules and a worked example: APA, MLA, Chicago and Harvard.
Does it make in-text citations?
Not yet. The short form in your text is usually the first author's last name and the year (APA and Harvard) or the last name and page (MLA), which you can take from the reference.
Is my list saved?
No. The list stays while this page is open and is gone when you close it, so copy it into your document before you leave.