What Is Footnote?
A footnote is a note anchored to a superscript number in the text and printed at the bottom of the same page. Chicago style is built on them, and they also carry explanatory asides too long for a sentence. Readers glance down, get the full source details, and return to your argument. This page unpacks the definition, the mistakes graders see most, and a worked example you can pattern-match against your own draft.
James Parker, MLS
Citation & Formatting Reviewer · Master of Library Science; 9 years as a reference librarian coaching APA, MLA and Chicago styles
Quick answer
A footnote is a note anchored to a superscript number in the text and printed at the bottom of the same page. Chicago style is built on them, and they also carry explanatory asides too long for a sentence. Readers glance down, get the full source details, and return to your argument.
On this page · 4 sections
The definition, precisely
A footnote is the citation machinery of note-based styles. A small superscript number sits at the end of the sentence that borrows material, and the matching note at the bottom of the page carries the source details: author, title, publication facts, page. Chicago's notes-bibliography system is the native habitat, which is why history, philosophy and theology papers bristle with them. APA 7 and MLA 9 allow footnotes only for content notes — explanatory asides — not for routine citations. The number usually follows punctuation: after the period in Chicago, after the closing quotation mark when quoting.
First appearance versus later ones is the rule students trip over. The first note for a source gives the full form — author's full name, title, publication facts, and the page — while every later note shortens to the author's last name, a two-to-four-word title, and the page. Chicago 17 prefers that shortened form over the older habit of stacking Latin abbreviations. Word processors handle the numbering: References, then Insert Footnote in Word, or Insert, then Footnote in Google Docs. The numbers renumber themselves when notes move, which is why manual superscripts are a trap.
Content footnotes are the other job. When a caveat, a competing statistic, or a tangential source would derail a paragraph, a note lets you park it below the text where interested readers can find it. Professors tend to like a good content note because it shows you read around the topic, but the tolerance is low: one or two sentences per note, rarely more than a few across a paper. If the material matters to your argument, it belongs in the body.
The four mistakes graders see most
Every one of these shows up in a stack of sixty papers — usually more than once. Each pairs the error with the fix, so the table doubles as a pre-submission check.
| Common mistake | The fix |
|---|---|
| Using footnotes for citations in an APA or MLA paper. | Those styles are parenthetical; footnotes there are for content notes only. Match the assigned citation system. |
| Giving the full citation in every single note. | First note is full, later notes shorten to author, short title, page. Chicago 17 prefers this over ibid chains. |
| Typing superscript numbers by hand and renumbering after edits. | Use Insert Footnote in Word or Google Docs so the numbering repairs itself when notes move. |
| Omitting the bibliography because 'the footnotes cover it'. | Notes-bibliography style requires both: every cited source appears in the notes and again in the final bibliography. |
A worked example
A history paper cites a book three times. Note 1 gives the full form: Marcus Reyes, Grain and Rail: The Midwest Wheat Economy, 1865-1900 (Lincoln: University of Nebraska Press, 2019), 88. Note 4 shortens to Reyes, Grain and Rail, 104. Note 7 shortens again, 112. A content note after the paragraph parks a tangent: 'Regional tonnage figures vary by up to a fifth; see the census tables cited in note 2.' The bibliography at the end repeats the full form once, alphabetized.
Pattern-match your own draft against this example rather than against the definition: concrete cases transfer better than abstract rules, and the example shows what the rule looks like when it is done right.
How footnote differs from its neighbors
A footnote is not an endnote; the note format is identical and the location is the difference — page bottom versus a Notes page at the back. It is not a bibliography entry either: the entry lists full publication data with no page reference and no shortened forms, while notes carry page numbers and can carry commentary. And it is not an in-text citation: APA's (Reyes, 2019) does the same job inline, with no superscript and no interruption to the page's layout at all.
Boundary confusion is where most grading deductions live: the term is understood roughly but applied against the wrong neighbor. Pin the boundary above and the term stops being fuzzy in practice, which is what the rubric is actually testing.
What's your next step?
Two taps to the exact page that unblocks this paper.
The 30-second check
Skim the four mistakes above against your draft. Any hit is a fix you can make in minutes — and the format row of the rubric is where they all live.
Run it through the tool
The free citation generator handles the mechanical half of this term — check it before you submit.
Open the toolRelated term: DOI — the neighbor this term is most often confused with. Reading the pair together is how the boundary sticks.
Frequently asked questions
4 answered1When should I use footnotes?
Whenever the assigned style is Chicago's notes-bibliography system — history, philosophy, art history and theology default to it. In APA or MLA, reserve footnotes for content notes: a caveat, a tangential source, or a thank-you the body text cannot hold. Check the syllabus first; the style is a course-level decision.
2How do I insert footnotes in Word or Google Docs?
In Word, place the cursor after the punctuation and choose References, then Insert Footnote — the number and the bottom-of-page note appear together. In Google Docs, use Insert, then Footnote. Both renumber automatically when notes shift, so never fake the superscript with manual formatting.
3What goes in the first footnote versus later ones?
The first note for each source uses the full form: author's complete name, full title, publication facts, and the page. Later notes shorten to the last name, a brief title, and the page. Chicago 17 favors this shortened style over piles of Latin abbreviations. Only the bibliography repeats the full form again.
4Do footnotes count toward the word count?
Usually not: most instructors count body text from first paragraph to conclusion and exclude notes, though conventions vary by course. Assume they do not count and keep notes lean anyway — a paper bloated with 300 words of asides reads as padding either way.
James Parker, MLS
Citation & Formatting Reviewer · Master of Library Science; 9 years as a reference librarian coaching APA, MLA and Chicago styles