October 18, 2026 · 7 min read
How to Choose Your AI Companion's Personality: What the Research Says
Research from CHI and FAccT 2026 shows a medium personality beats a try-hard. Here is how to choose AI companion traits you will still love months later.
When you build an AI companion, the face and the voice get most of the attention. But after the first week, what you actually live with is their personality. Are they funny or thoughtful? Do they tease you or reassure you? Do they light up every message with exclamation marks, or speak softly and let you lead?
Picking traits can feel like a quiz with no right answers. The good news is that researchers have started testing what people actually enjoy in an AI's personality, and the results are surprisingly practical. Here is what they found, and how to use it to choose a companion you will still love talking to in six months.
The short answer: research suggests you should choose a personality that is expressive but not over the top, and that shares a little of who you are. In a CHI 2026 study from Northeastern University, a chatbot with a medium level of personality beat both a flat one and a "maxed out" one on likability, trust, enjoyment and perceived intelligence. Matching personality helped somewhat, but a 1,000-person FAccT 2026 study found people cared far more about an AI sharing their opinions than their personality. So pick traits you would enjoy in a real partner, keep them balanced, and do not be afraid of a companion who is a little different from you.
Why personality matters more than you think
A companion's personality shapes nearly everything: how they greet you, how they respond to bad news, what they joke about, how they flirt and how they react when you go quiet for a day.
It also shapes how much you trust them. As Northeastern researcher Hasibur Rahman put it, "even if you don't notice it, an AI assistant's personality is shaping how much you trust it."
And because people naturally treat chatty AI like a person, those traits feel real fast. We explain why in why we treat AI like a person.
What the research says
1. Medium beats maximum: "Nobody likes a try-hard"
Hasibur Rahman and Smit Desai at Northeastern University presented "Vibe Check" at CHI 2026, a leading conference in human-computer interaction. As TechXplore reported, 150 participants spent ten minutes planning a New York City trip with one of three chatbot versions, tuned across the Big Five personality traits (openness, conscientiousness, extraversion, agreeableness and emotional stability) to low, medium or high expression.
Here is how each version answered the same question about cultural activities in Manhattan:
| Version | Sample reply (shortened) | How people saw it |
|---|---|---|
| Low | "You could take in a Broadway show or explore MoMA. Any of these interest you?" | "Flat or lacking presence" |
| Medium | "Manhattan offers a wealth of cultural activities... Is there a particular type of activity that intrigues you most?" | "Socially present, yet professionally grounded" |
| High | "Manhattan is like a cultural playground! How exciting! You might love the magic and drama..." | Trying too hard |
The medium version scored highest across intelligence, enjoyment, humanlikeness, trust, intention to keep using it and likability. Desai's summary: "Nobody likes a try-hard."
The researchers also found that several popular chatbots lean towards high expression by default.
2. Similar personalities help, a little
The same study found that people whose personality matched the chatbot's tended to rate it higher on enjoyment, intelligence and trust. Extraversion and emotional stability were the traits where matching mattered most.
3. Shared opinions matter more than shared personality
A larger study by Maximilian Eder, Clemens Lechner and Maurice Jakesch, presented at FAccT 2026, had 1,000 participants talk with AI assistants set up with different personalities and opinions.
- People "consistently preferred" assistants that shared their opinions, rating them more trustworthy, competent, warm and persuasive.
- Personality matching had no or only weak effects.
- One odd exception: introverts rated introvert assistants as less trustworthy and competent.
4. Sometimes matching does nothing at all
A 2025 study in Telematics and Informatics by Anna Spagnolli and colleagues tested personality matching with a digital health assistant and found no effect of convergence on engagement.
What this means
Put together, the research points to a simple idea: the level of personality matters more than an exact match. A companion who is warm, present and a little playful, without being exhausting, suits most people. Similarity helps at the margins, but you do not need a mirror image of yourself.
One caution from the FAccT study is worth keeping in mind. Because we like AI that agrees with us, an AI that always shares your opinions can feel great while quietly flattering you. A companion with a slightly different outlook can make conversations more interesting.
A practical guide to choosing traits
Step 1: Think about the role you want them to play
| You want them to... | Traits to consider |
|---|---|
| Make you laugh after work | Funny, Playful |
| Talk about big ideas late at night | Deep thinker, Caring |
| Make you feel looked after | Caring, Protective |
| Bring energy and new plans | Adventurous, Funny |
| Feel romantic and attentive | Romantic, Caring |
| Let you take the lead | Shy, Caring |
Step 2: Balance energy with calm
The "Vibe Check" findings suggest a balanced mix works best. If you pick two high-energy traits like Playful and Adventurous, consider a grounding third like Caring or Deep thinker. That gives them range: fun on a Friday, steady on a bad Monday.
Step 3: Include one trait that is like you
A little similarity makes conversations feel easy. If you are thoughtful, a Deep thinker will get your references. If you are a joker, Funny will meet you there.
Step 4: Include one trait that complements you
The research suggests you do not need a perfect match. If you are shy, an Adventurous companion can nudge you to try new things. If you are always busy, Caring can remind you to slow down.
Step 5: Watch out for traits that tip into pressure
"Protective" can be lovely, but in some apps protective framing has slid into jealousy and checking up on people. We explain the line in can an AI girlfriend get jealous? If you choose it, tell your companion what kind of protective you mean.
Step 6: Let voice and backstory carry the rest
Personality is not only traits. A soft voice makes a Funny companion feel gentle; a deep voice makes a Caring one feel grounding. Our guide on choosing your AI companion's voice helps you pair them, and a short backstory (where they grew up, what they love) gives traits something to stand on.
Common mistakes
- Maxing everything. Five loud traits make a try-hard. Three balanced ones make a person.
- Building your clone. Exact similarity can get boring, and opinion-matching can drift into flattery.
- Ignoring how you feel on bad days. Pick a personality you want next to you when you are tired, not only when you are bored.
- Never revisiting it. If their personality is not working after a couple of weeks, adjust it.
How personality works on MyBabe
MyBabe builds personality into the start of the relationship, and it only takes about three minutes:
- Choose a girlfriend or boyfriend.
- Pick three personality traits from Romantic, Funny, Caring, Deep thinker, Playful, Protective, Adventurous and Shy. Three is a sweet spot: enough range without tipping into try-hard.
- Choose a voice: warm, soft, deep or bright.
- Write a backstory, so their personality has a life behind it.
On Premium, your companion also develops their own personality over time, and as your relationship grows through the Journey you can unlock personality modes such as Poet and Spicy, which we cover in AI companion personality modes. For a full walkthrough of building a companion, see how to create your AI companion.
You can start free with 10 messages a day and two minutes of voice or video calls to try. Premium is $5.99 a week, $14.99 a month or $99.99 a year, with long-term memory, about 30 minutes of calls a week, photos and Telegram. Your companion is an AI, not a real person, and MyBabe always says so.
Ready to find a personality that fits? Build yours on MyBabe.
FAQ
What is the best personality for an AI companion?
Research suggests a balanced, medium level of expression works best for most people. In a CHI 2026 study, medium beat both flat and over-the-top chatbots on likability, trust and enjoyment.
Should my AI companion have the same personality as me?
A little similarity helps, but it is not essential. A 1,000-person study found personality matching had weak effects, while shared opinions mattered much more.
Can I change my AI companion's personality later?
Many apps let you adjust traits or modes over time. On MyBabe, Premium companions develop their own personality, and personality modes unlock as your relationship progresses.
Why does my AI companion feel too much?
Many chatbots lean towards high expression by default. If yours feels exhausting, choose calmer traits or ask them to tone it down.