OpenAI says ChatGPT will now avoid em dashes if users tell it to; em dashes have become telltale signs that supposedly signals text written by AI
Sam Altman celebrates ChatGPT finally following em dash formatting rules The Economic Times : OpenAI fixes ChatGPT's em dash problem; ‘small-but-happy-win’ says Sam Altman Kahekashan / The Hans India : OpenAI Ends ChatGPT's Em Dash Quirk, Rolls Out New Group Chat Feature X: Sam Altman / @sama : Small-but-happy win: If you tell ChatGPT not to use em-dashes in your custom instructions, it finally does what it's supposed to do! @beffjezos : em dash should be called ai dash at this point Greg Kumparak / @grg : if they could just turn emdashes off by default so I could go back to using them* without judgement that would be great (* way too much, as I have for a thousand years) Gary Marcus / @garymarcus : if you can't even get ChatGPT to respect people's em-dash preferences, how the F are you going to solve alignment? Igor Babuschkin / @ibab : I'm seeing AI generated posts and replies everywhere now. ChatGPT has a few telltale signs that give away AI generated content. These will soon be post trained away. It's not about AI content being everywhere, it's about the fact that we'll soon lose the ability to tell! Bojan Tunguz / @tunguz : Our last defense against AI slop is now down. Ben Jammin / @xbenjamminx : This is the biggest improvement in AI that I've seen in the last two years. Drew / @imnotowned : Curing cancer right around the corner! @petetrainor : “Help me disguise the Ai-y-ness of my content.” Pierre-Olivier Carles / @pocarles : The most awaited feature since GPT‑3. Ryan Ferris / @thegoodtimeline : and here i was thinking @OpenAI purposefully kept em-dashes in, as way to detect slop/spam turns out chat just reaaaly loves em-dashes lol @artbrock34 : Oh, this made-my-day Ben Goggin / @benjamingoggin : If it took them this long to get ChatGPT to stop using em dashes, it definitely makes you wonder how long it will really take to address issues like encouraging suicide @kjovano : How much pollution will be created to fine-tune technology that isn't going to save people's lives? Neeraj Khandelwal / @neerajkh_ : ChatGPT launched the most important feature of 2025: no em-dashes. It works too. I checked. Always verify, then trust. 🤣 [image] Gary Marcus / @garymarcus : um, if you can't specify your em-dash preferrences, how the F are you going to solve alignment? Reid Southen / @rahll : You guys trust a technology that took them literally years to figure out how to get it to stop using em dashes? Okay then... Shuaichen Chang / @shuaichenchang : This reminds me of when Apple announced they launched five new emojis 🙂↔️ lol. But honestly, this is great progress. Getting LLMs to follow instructions at the token level is harder than it looks. Now I'm gonna try teaching it to talk without prompting itself into a new task Matt Biilmann / @biilmann : AGI! Becky Keene / @beckykeene : The ultimate goal is to normalize using em-dashes as humans again so those of us who write with them naturally aren't judged by the AI shamers. #AI Angela Gruber / @netzkolumnistin : Daily reminder: AI is not omnipotent but extremely situationally dependent. Ralph Brooks / @ralphbrooks : AI one step closer to being indistinguishable from human writing. Ali Spittel / @aspittel : I would like to start an emdash redemption campaign. Sincerely, someone who has been way overusing dashes since before ChatGPT. Minh Nhat Nguyen / @menhguin : im 70% convinced openai intentionally keeps the emdash as an easy way to watermark text written by ChatGPT. Kim-Mai Cutler / @kimmaicutler : Nooooo........ my child was reading the em dashes aloud as minus signs, as in “Bye MINUS have a nice day!” Sarah Catanzaro / @sarahcat21 : Sam, this is not small. Huge if true. Joshua March / @joshuamarch : Can everyone do this So I can go back to using em-dashes Marc Köhlbrugge / @marckohlbrugge : Best thing about this is that we can finally use em-dashes again without being accused of AI writing 🤣 Ben Golub / @ben_golub : Unfortunately this reduces it to only silver medal level on the IMO due to the strain of pushing so hard against its nature. Dror Poleg / @drorpoleg : A small step for ChatGPT — a giant leap for writers who love em-dashes. Yana Welinder / @yanatweets : Only took 3 years to teach AI to stop using em dashes. Now the real test: how long until humans stop treating every em dash as an AI tell? Gordon Wintrob / @gwintrob : All the personalization you need: When writing text, avoid em-dashes and other common “AI slop” patterns. Dominik Kundel / @dkundel : As a user of em-dashes I'm way too invested in AI writing less with em-dashes 😄 Chris Maddern / @chrismaddern : biggest — chatgpt — upgrade — ever AshutoshShrivastava / @ai_for_success : @sama Finally it's over... [image] @koltregaskes : @sama AGI has been achieved. 😜 Rhys / @rhyssullivan : feel free to hit me up next time [image] Chip Huyen / @chipro : Sam!!! [image] Omar Khattab / @lateinteraction : instruction following is hard @theo : Fun fact: there are 23 em-dashes in the GPT 5.1 announcement post [image] Abby Stylianou / @abby621 : I went through my @CVPR submission last night to remove any em dashes I had written because I didn't want reviewers to think I had used LLMs for my writing. Look forward to a day when I can use em-dashes again without fear. Simon Hedlin / @simonhedlin : @sama Great! Hopefully this means that those of us who like em-dashes (the most versatile punctuation mark) eventually can start using them again without being falsely accused of relying on unedited AI writing. Brian Lovin / @brian_lovin : AGI has been achieved internally Arin Hanson / @egoraptor : I find what's being unsaid here disturbing: the reason removing em-dashes from ChatGPT responses is a “win” that is worthy of an announcement is that em-dashes are primarily used to sniff out if a published work was written by ChatGPT. What purpose does this serve except to more Bluesky: Harry McCracken / @harrymccracken.com : Excessive use of em dashes would be about #25 on my list of telltale signs something was written by AI. And it's far from the most annoying one. — (My personal #1 annoying telltale sign is endless use of “It wasn't just x, it was also y”-type constructions.) techcrunch.com/2025/11/14/o... @pileofgarbage.net : This is fucking pathetic and at stark odds with the magical AGI fantasy perpetuated by Altman and his ilk. Focussing on what is ultimately aesthetics to the extent that you're micro-managing the entire gen AI model is literally the furthest possible point from AGI. arstechnica.com/ai/2025/11/f... Richard Lawler / @rjcc : There are several pretty easy tells for ai writing, em dash overuse isn't really one of them. — One of the reasons they're easy tells is because people who are using chatbots to write, also aren't good at editing. [embedded post] Nitish Pahwa / @nitishpahwa.com : the thing about chatbots is that their predictive engines will engender certain patterns more often than not. the em dash factor is a meme; there are tells that go far beyond that [embedded post] Alex Knapp / @thealexknapp : As an enthusiastic em-dasher, I really resent that this has come to be a sign of AI-generated copy. [embedded post] @scriban : This is all—and I say this with respect—so very stupid. [embedded post] Mastodon: @Khrys@mamot.fr : Forget AGI—Sam Altman celebrates ChatGPT finally following em dash formatting rules — https://arstechnica.com/... this “small win” raises a very big question: If the world's most valuable AI company has struggled with controlling something as simple as punctuation use after years of trying … @ai6yr@m.ai6yr.org : But—stick with me here—there might be a reason for using an em dash? Some of us—including myself—really like using the emdash. Why is an em dash—which I love so much—a problem? 🤪 — TechCrunch: OpenAI says it's fixed ChatGPT's em dash problem — https://techcrunch.com/... Forums: r/artificial : Forget AGI—Sam Altman celebrates ChatGPT finally following em dash formatting rules
Context & Ripple Effects
OpenAI has steadily made prompting and configuration part of how users shape model behavior, from its use of prompt engineering to steer DALL-E 3 to the rollout of task-specific custom GPTs. This update extends that control to a small but highly visible writing convention.
The change matters because repeated stylistic patterns can become social shorthand for machine-written prose. Coverage of recurring quirks in AI-generated writing places the em-dash issue in a broader feedback loop between model output and human writing habits.
First-order effects
- ChatGPT users can make a formatting preference in custom instructions stick, reducing unwanted em dashes in generated drafts.
- OpenAI removes one conspicuous output habit that users may associate with ChatGPT, while leaving the choice with users rather than changing the punctuation rule universally.
Second-order effects
- Other assistant providers face a clearer expectation that persistent preferences should cover fine-grained style controls, not just task or tone.
- Writers using AI for publishable copy gain another way to align drafts with house style, but punctuation alone becomes a less useful shortcut for judging a text's origin.
Third-order effects
- As model prose acquires recognizable habits, configurable output style is likely to become a baseline product surface rather than a cosmetic extra.
- The broader attribution problem may deepen: when systems can suppress visible tells, readers and publishers must rely less on stylistic cues and more on provenance or editorial process where origin matters.
The trend: Generative-AI products are moving from generic fluent output toward persistent, user-directed controls that make machine-written text easier to blend into established workflows and styles.