Free Title Case Converter
Convert your paper, thesis or headline to correct APA, MLA, Chicago, AP or sentence case in one paste. Every style is shown side by side, following the actual capitalization rules of each style guide: major words up, articles and the right prepositions down, subtitles after colons handled, acronyms untouched. Copy the version your journal, department or editor expects.
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How to convert a title in three steps
Paste your title
A paper title, a chapter heading, a headline or a whole list of references, one title per line.
Compare the styles
APA, MLA, Chicago, AP and sentence case are converted at once, so the differences are visible instead of guessed.
Copy the right one
Each row has its own copy button. Hover the info icon to see the rule set the row follows.
Why this title case converter is different
Every style at once
No style dropdown to configure. All five conversions run side by side, which is the fastest way to spot how the rules differ for your exact title.
Real style-guide rules
Not naive capitalize-every-word. APA's four-letter rule, MLA's lowercase prepositions, subtitle capitalization after colons and hyphenated compounds are all applied.
Acronym and term safe
DNA, ANOVA, COVID-19, mRNA and iPhone come through exactly as typed in every style, including sentence case.
Built for reference lists
Paste multiple titles, one per line, and convert them together: handy when an APA reference list needs sentence case across dozens of entries.
Title capitalization: small rules, visible signals
Capitalization is one of the first things an experienced reader checks without noticing they are checking it. A submission whose title mixes conventions, or whose reference list capitalizes article titles that APA wants in sentence case, signals a manuscript that was assembled in a hurry. None of this affects the science, but reviewers and editors read hundreds of manuscripts, and consistent formatting buys a more generous first read.
The rules themselves are simple but incompatible. Every major style capitalizes the first word, the last word and all nouns, verbs, adjectives, adverbs and pronouns. The disagreement is over the small words. APA draws the line at length: anything of four letters or more is capitalized, including prepositions such as "Between" and "With". MLA and Chicago draw the line at function: prepositions stay lowercase no matter how long. AP, built for headlines, capitalizes almost everything of four letters or more. The same title is therefore correct in one venue and wrong in the next, which is why this converter shows every style at once instead of asking you to pick one and trust it.
Sentence case is the other half of the story. APA reference lists put article and book titles in sentence case while journal names keep title case, and a growing number of science journals, including Nature, use sentence case for article titles everywhere. When you convert to sentence case, keep an eye on proper nouns: no tool can know that a lowercase "turing" is a person, so names need a manual pass after conversion.
For the rest of the manuscript, capitalization is only one of the surface signals that shape how your writing is received. Our guide on improving your academic writing style covers the habits that matter beyond the title page.
The capitalization rules at a glance
Where the four title-case styles agree and where they part ways.
| Word type | APA | MLA | Chicago | AP |
|---|---|---|---|---|
| Articles (a, an, the) | lower | lower | lower | lower |
| Short prepositions (of, in, to, by) | lower | lower | lower | lower |
| Long prepositions (between, through) | Cap | lower | lower | Cap |
| Coordinating conjunctions (and, but, or) | lower | lower | lower | lower |
| Short verbs and pronouns (is, be, it, our) | Cap | Cap | Cap | lower* |
| First and last word | Cap | Cap | Cap | Cap |
*AP lowercases every word of three letters or fewer unless it opens or closes the headline.
Six capitalization mistakes reviewers actually see
Drawn from the corrections that come back most often in copy editing and peer review.
Capitalizing every word
Word processors offer "Capitalize Each Word", and the result capitalizes "Of", "The" and "In" where every style guide lowercases them. It is the most visible capitalization error in submitted titles because it looks almost right.
Lowercasing short verbs
"Is", "Be" and "Are" are verbs, and every title-case style capitalizes verbs regardless of length. Writers who learned "lowercase short words" as the rule routinely get "What is It Like to Be a Bat" wrong in both directions.
Missing the subtitle capital
The first word after a colon starts the subtitle and is capitalized in every style, even when it is an article: “A Longitudinal Study”, not “a longitudinal study”. The same applies after a question mark inside a title.
Losing acronyms in sentence case
Converting a title to sentence case with a naive lowercase function turns DNA into dna and COVID-19 into covid-19. Acronyms, initialisms and mixed-case terms such as mRNA keep their capitals in every case style.
Title-casing the reference list
In APA references, article and book titles take sentence case while the journal name keeps title case, in the same entry. Applying one style to the whole reference is among the most common formatting corrections copy editors make.
Inconsistent hyphenated compounds
"First-year" appears as "First-Year" in one heading and "First-year" in another. In APA and MLA, both halves of a hyphenated major compound are capitalized; pick the rule once and let a converter hold the line.
Who uses the title case converter
Researchers and PhD students
Format paper titles, running heads and APA-style headings correctly before submission, and fix reference-list capitalization in bulk.
Students
Get essay and thesis titles right in the style your department requires, with the rule differences visible instead of memorized.
Journal authors and editors
Match each journal's house style quickly: title case for one venue, sentence case for the next, without re-reading the author guidelines.
Writers and marketers
AP headline case for articles, newsletters and press releases, converted in a second rather than debated in review.
Title case converter FAQs
Which capitalization style should I use?
Why does APA capitalize "Between" but MLA lowercase it?
How are acronyms and technical terms handled?
Is the title case converter free to use?
The title is thirty seconds. The manuscript is the work.
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