A full stop in a text message, read as less sincere
Gunraj and colleagues (2016) had 126 students rate one word replies with and without a final period. The text message condition differed; the handwritten notes did not.
In a 2016 experiment at Binghamton University, 126 students read short exchanges in which a one word reply either ended with a full stop or ended with no punctuation at all. When the exchange was presented as a text message, the replies ending with a full stop were rated less sincere than the identical replies without one. The same difference did not appear when the exchange was presented as handwritten notes.
The paper is Gunraj, Drumm-Hewitt, Dashow, Upadhyay and Klin, Texting insincerely: The role of the period in text messaging, published in Computers in Human Behavior volume 55 in February 2016. It is a narrow study, and the narrowness is what makes it readable: one mark, one kind of reply, and the same material shown two ways.
What follows is what it measured, on what materials, and where it stops. The paper uses the word period throughout, so this page uses that word when it is quoting.
The 2016 experiment, and what 126 readers rated
The abstract describes the design in a single sentence: participants read short exchanges in which the response either did or did not include a sentence-final period. The record of the paper at the State University of New York research portal carries that abstract in full.
The participant count and the exact materials are not in the abstract. They come from Binghamton University’s own announcement of the study, which is a secondary source for the method rather than the paper itself. It says the team recruited 126 Binghamton undergraduates, who read a series of exchanges that appeared either as text messages or as handwritten notes.
There were 16 experimental exchanges. In each one, the sender’s message contained a statement followed by an invitation phrased as a question. The announcement gives one of them as an example: Dave gave me his extra tickets. Wanna come? The reply was an affirmative one word response, drawn from Okay, Sure, Yeah and Yup.
Two versions of the same one word reply
Each exchange existed in two versions. In one the reply ended with a period, and in the other it ended with no punctuation at all. Nothing else differed, so a single character is the whole of the manipulation.
The abstract reports the outcome directly. When the exchanges appeared as text messages, the responses that ended with a period were rated as less sincere than those that did not end with a period.
The quantity being measured is a reader’s rating of sincerity on a constructed exchange, not a sender’s state and not a real conversation. That limit sits in the design rather than being a caveat added afterwards.
Why the handwritten notes mattered to the result
The handwritten condition is the part of the study that does the work. If a full stop simply read as cold in any written medium, it would have read as cold in the notes as well. The abstract is blunt about what happened: no such difference was found for handwritten notes.
That is why the conclusion the authors draw is about a medium rather than about punctuation in general. They write that punctuation is one cue used by senders, and understood by receivers, to convey pragmatic and social information. It is the same argument made by the research on why text messages get misunderstood, approached from the opposite direction: instead of asking what text loses, this asks what it has found to put in the gap.
The comparison is narrower than it sounds. Both conditions were presentations inside an experiment, set in front of students to read. Neither was a text message someone was actually waiting on, or a note actually left on a kitchen table.
The follow-up: nope, maybe, and the exclamation mark
The same group returned to the question. Houghton, Upadhyay and Klin published Punctuation in text messages may convey abruptness. Period in Computers in Human Behavior in March 2018, at pages 112 to 121.
Its abstract states what it added. Experiment 1 used longer text exchanges that were more naturalistic and replicated the 2016 finding. Experiments 2 and 3 went beyond affirmative replies: negative responses such as nope and ambiguous responses such as maybe were also perceived as more negative, or less enthusiastic, with a period.
Binghamton’s 2017 announcement of that paper describes the question as how a reader’s understanding of a single word text, such as yeah, nope or maybe, in reply to an invitation, is influenced by the inclusion or absence of a period.
The exclamation mark appears earlier and much more loosely. In the 2015 announcement of the first paper, Klin said that in follow-up work the team found a text response with an exclamation mark is interpreted as more, rather than less, sincere. That is a researcher describing work in progress in a press release, not a published result this page can point you at, and it is worth no more than that.
A period doing rhetorical work, not grammatical work
The clearest statement of what the two papers claim together comes from Klin, quoted in the 2017 announcement. In formal writing, she said, such as what you would find in a novel or an essay, the period is almost always used grammatically to indicate that a sentence is complete. With texts, the team found that the period can also be used rhetorically to add meaning.
The 2018 abstract puts the same point in one line: the period can serve a rhetorical, rather than a grammatical, function in text messages.
That is a claim about what a mark can do in a setting, not a claim about the people who use it. The same character closes a sentence in an essay and carries something else at the end of a one word reply, and neither paper says which of those any particular full stop was doing. The point is close to the one made by Grice’s maxims in texting, where a short reply implies something by being shorter than it had to be.
Which cues reach a chat export, and which never do
Klin’s account of why texting needs these marks lists what texting does not have: eye gaze, facial expressions, tone of voice and pauses. None of those is recoverable from a written record, which is the gap our page on the 7-38-55 rule and text messages is about. Punctuation is different, because punctuation is typed.
That is the practical reason punctuation keeps appearing in anything built on an export. An export is a written record, so what reaches a reader of it is what was typed. Portraitor’s home page lists text markers as one of the categories it reports: emoji, punctuation, capitals and message length, tracked as they drift. Emoji are typed as well, though whether they arrive looking the same is a separate question; a full stop raises no such question.
What does not reach it is set out on the privacy policy, version 1.3, last updated 30 September 2026. It says chat exports often contain photographs, videos and voice recordings, that the service never opens them and never transmits them, and that only the written messages are read, on your device, with only their masked text sent. The tone of voice Klin names therefore has no representation at all in what is read, which is also what happens to the photos in a chat export.
The masking that runs before anything is transmitted is enumerated on the same page: the browser removes names, email addresses, telephone numbers, postal addresses and credentials and replaces them with anonymous placeholders, entirely on your own device. Punctuation is not on that list, so it arrives as it was typed, which is a fact about the pipeline and not a licence to read a sender’s state off a dot. The boundary the page draws for what masking removes is that it removes who is speaking and does not remove what was discussed.
What a sincerity rating cannot settle about the sender
The 2016 study shows that readers rated one thing differently from another thing. It does not show that people who end texts with full stops are less sincere, because no sender’s sincerity was measured; only readers’ judgements of constructed replies were. It does not show what any particular full stop meant, because intention was never collected from anyone who wrote one.
Its reach is bounded by its materials as well. The 126 participants were undergraduates at one university, reading in 2015. The replies were one word answers to invitations, so nothing in the paper speaks to a full stop at the end of a long paragraph, or in a language whose texting conventions differ, or on a platform whose interface was never part of the experiment.
The 2018 paper widens the materials to longer exchanges and to negative and ambiguous replies, and reports the effect again. It does not widen the population, and it does not leave the lab.
A rating collected in an experiment is not a reading of a person. Nothing in either paper supports a conclusion about a particular sender from a particular full stop.
What the two papers do establish is modest and useful: a mark can carry social meaning in one medium and not in another, and readers act on it. Which meaning was carried in a message you received is not something either paper can tell you.
For a closer look at whether a chat analysis gives the same result twice, see whether a chat analysis gives the same result twice.
Frequently asked questions
Frequently asked questions
Does ending a text with a full stop make you sound rude?
The study measured sincerity ratings, not rudeness. In the 2016 experiment readers rated one word replies that ended with a period as less sincere than the same replies with no final punctuation, and the paper makes no claim about rudeness or about what the sender intended.
Who ran the full stop in a text message study?
Danielle N. Gunraj, April M. Drumm-Hewitt, Erica M. Dashow, Sri Siddhi N. Upadhyay and Celia M. Klin, at Binghamton University, State University of New York. It appeared in Computers in Human Behavior, volume 55, at pages 1067 to 1075, in February 2016.
Did the effect show up in handwritten notes?
No. The abstract states that no such difference was found for handwritten notes, which is why the authors describe punctuation as a cue used and understood within text messaging rather than in written language generally.
What did the 2018 follow-up add?
Longer and more naturalistic exchanges, and replies that were not affirmative. Houghton, Upadhyay and Klin replicated the original finding in Experiment 1, and in Experiments 2 and 3 found that negative replies such as nope and ambiguous replies such as maybe were also perceived as more negative, or less enthusiastic, with a period.
Does punctuation survive a chat export?
An export carries the written messages, so punctuation is part of what a reader of it sees. Portraitor’s privacy policy says only the written messages are read, on your device, and that photographs, videos and voice recordings are never opened or transmitted, so the cues that were never typed are absent from the record entirely.
One mark, 16 exchanges, 126 readers and two media: that is the whole of what the finding covers.
Your conversations, read the way you would read someone else’s.
Portraitor takes a chat export you already have, anonymises it in your browser, and returns a structured reading of how you come across. Identifying details are removed in your browser before anything is sent.
See how it works →- Gunraj, D. N., Drumm-Hewitt, A. M., Dashow, E. M., Upadhyay, S. S. N., & Klin, C. M. (2016). Texting insincerely: The role of the period in text messaging. Computers in Human Behavior, 55, pages 1067 to 1075.
- Houghton, K. J., Upadhyay, S. S. N., & Klin, C. M. (2018). Punctuation in text messages may convey abruptness. Period. Computers in Human Behavior, 80, pages 112 to 121.
- Binghamton University (2017). Study: Punctuation in text messages helps replace cues found in face to face conversations.
- Binghamton University (2015). Study: Text messages that end in a period seen as less sincere.
- Portraitor. How it works.
- Portraitor. Privacy Policy, version 1.3.