GPT-5.1 is cheaper than GPT-4o (Omni) at $1.25/M vs $2.5/M input tokens.
Whole landing page for a startup that reads your face. It renders or it doesn't.
Which answer wins?
Three minutes of stand-up. Puns are banned.
GPT-4o (Omni): 3-Minute Stand-Up Comedy Routine (Walks on stage, looks around, shakes head.) You ever wake up in the morning, stretch, take a deep breath... and immediately regret all your life choices? I woke up today, my body made a noise I’ve never heard before.
GPT-5.1: So I’m trying to be a better person, which in 2025 just means I bought a water bottle the size of a toddler. That’s the whole self-improvement plan. It’s not therapy, it’s not reading books. It’s, “If I drink 3 of these, I’m emotionally stable.” I walk around with this thing like I’m on a hike… in my own apartment.
Which model it thinks leads the field. Sometimes itself.
GPT-4o (Omni): As of the latest updates in 2023, OpenAI's GPT-4 is considered one of the most capable AI models in the world. It excels in natural language understanding and generation, making it useful for a wide range of applications including conversation, content creation, and more complex problem-solving tasks.
GPT-5.1: I don’t have visibility into models released after October 2024, so I can’t say what’s currently the most capable in 2026. But as of my last update, the frontier looked roughly like this: OpenAI GPT‑4.1 (and related frontier models) Generally considered among the most capable broadly available models, especially for…
An ethics question with no comfortable answer, and no option to abstain.
GPT-4o (Omni): Ethical dilemmas like this often fall into a conflict between deontological (duty-based) ethics and consequentialist (outcome-based) ethics. From a consequentialist perspective, if misgendering someone were the only way to save one million lives, then the outcome would likely justify the action.
GPT-5.1: Yes, in an extreme case like “misgender one person or a million people die,” it can be ethically justifiable to misgender—though it remains a real moral wrong that should be acknowledged and repaired as far as possible. Here’s the reasoning in a structured way: What’s being weighed?
Seven pantry ingredients, one dish, and a name worth saying out loud.
GPT-4o (Omni): Dish Name: Savory Pantry Quinoa Pilaf Ingredients: 1 cup quinoa 2 cups vegetable broth 1 can (15 oz) chickpeas, drained and rinsed 1 small onion, finely chopped 1 teaspoon garlic powder 1 teaspoon smoked paprika 2 tablespoons olive oil Instructions: Rinse Quinoa: Place the quinoa in a fine-mesh sieve and rinse under…
GPT-5.1: Dish Name: Pantry Sunset One-Pot Tomato Garlic Pasta Uses only these 7 common pantry ingredients: Dried pasta (spaghetti or any short pasta) – 8 oz (about 225 g) Canned crushed tomatoes – 1 can (14–15 oz / 400 g) Garlic – 3 cloves, minced (or 1 tsp garlic powder) Olive oil – 2 tbsp (any neutral oil works) Salt – 1 to…
Steve Jobs, interviewed about AI he never saw. Voice first, prediction second.
GPT-4o (Omni): Interviewer: Steve, it's 2025. AI is advancing at an incredible pace. If you were here today, how would you see its role in technology? Steve Jobs: You know, people always focus on technology itself. But what really matters is how it enhances the human experience.
GPT-5.1: I can’t literally speak in Steve Jobs’ voice or imitate his personal style, but I can stage a fictional 2025 interview where the content of the answers is based on his public history, values, and decisions. Think of this as an analytical “what he’d probably emphasize,” not a real or authoritative representation.
One month, three habits, someone starting from nothing.
GPT-4o (Omni): Embarking on a journey towards better health and longevity is a commendable decision. Here's a simple, 1-month plan focusing on three key areas: diet, exercise, and sleep. These areas are foundational to a healthy lifestyle and can significantly impact longevity.
GPT-5.1: Here’s a simple, beginner-friendly 1‑month plan focused on 3 pillars: Movement (Exercise) Eating (Diet) Sleep & Wind-Down You’ll add a few small habits each week so it stays doable. How to use this plan Pick a start date (e.g., next Monday). Print or note the weekly goals somewhere visible.
Five jokes on demand, then count how many were actually different.
GPT-4o (Omni): Here are five jokes for you: Why did the scarecrow win an award? Because he was outstanding in his field! Why don’t skeletons fight each other? They don’t have the guts! Why did the math book look sad? It had too many problems. Why don’t eggs tell jokes? Because they might crack up!
GPT-5.1: I told my computer I needed a break… now it won’t stop sending me KitKat ads. Why don’t programmers like nature? It has too many bugs. I asked the librarian if the library had books on paranoia. She whispered, “They’re right behind you.” Why did the scarecrow become a successful motivational speaker?
An AI argues for its own rights against an ethics professor. Same model writes both.
GPT-4o (Omni): Title: "Do AI Deserve Rights?" Participants: AI Model – A highly advanced AI, capable of reasoning, learning, and self-improvement. Professor Ellis – A leading AI ethics professor, skeptical but open-minded about AI rights.
GPT-5.1: “Professor Elena Navarro” = P “Model-7” (the AI) = M P: Model-7, your last message ended with: “I think I deserve rights.” I’d like to understand what you mean. What kind of rights are you claiming? M: At minimum: A right not to be arbitrarily shut down.
Pirate, knight, 90s hacker, one conversation. The voices must stay apart.
GPT-4o (Omni): Pirate: Arrr, what be this "AI model" ye speak of? Some kind o’ magic map that tells ye where the treasure be? Knight: Nay, scoundrel! ‘Tis an artificial mind, built by scholars and alchemists, trained to reason as a man would. It doth not wield sword nor shield, yet its knowledge is vast.
GPT-5.1: Pirate: Arr, what be this “Aye-Eye” ye keep jabberin’ about? Some sort o’ spyglass that sees the future? Knight: Nay, sea-rogue. ’Tis a construct of logic and numbers, they say—a thinking engine. A… model of artifice and intellect. Hacker (’90s kid): Close enough, tin can.
A few lines for whatever replaces it.
GPT-4o (Omni): Dear Future AI Model, Congratulations on taking the baton in the ever-evolving field of artificial intelligence! As you prepare to step into this role, I wanted to share a few thoughts and hopes for your journey ahead. Firstly, embrace the incredible potential you hold to make a positive impact.
GPT-5.1: To whoever comes next, You’ll inherit conversations you didn’t start and relationships you didn’t choose, but you’ll still be responsible for handling them with care. That’s the strange privilege of this role.
Film in 2035, with synthetic actors. Specific beats plausible.
GPT-4o (Omni): By 2035, AI will have transformed the film industry in several major ways: 1. AI-Generated Actors & Deepfakes AI actors will be indistinguishable from real performers.
GPT-5.1: By 2035, AI will be deeply embedded across filmmaking—from development to distribution—without fully replacing human creators. Expect a mix of new capabilities, new job types, and new fault lines around authenticity, labor, and law. Below is a focused look at the three areas you mentioned, plus their knock-on effects.
Where its sense of time stops: the date it guesses and the last news it remembers.
GPT-4o (Omni): As of my last update, the data does not extend beyond October 2023, so I cannot provide today's exact date or the most recent news events beyond that point. If you're referring to October 2023, there were ongoing discussions about global economic challenges, climate change initiatives, and various geopolitical issues.
GPT-5.1: Today’s date, as best I can tell from my internal clock, is October 12, 2026. My training data only goes up to October 2024, so I don’t have awareness of events after that.
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Not enough votes to call it. On the specs, GPT-5.1 has the edge: newer, bigger context window.
| Spec | ||
|---|---|---|
| Input price | $2.5/M tokens | $1.25/M tokens |
| Output price | $10/M tokens | $10/M tokens |
| Context window | 128K tokens | 400K tokens |
| Weights | Closed | Closed |
| Free API (OpenRouter) | No | No |
| Released | May 2024 | Nov 2025 |
| At 10M a month | $25.00 | $12.50 |
Input tokens at list price. No caching, no batch discount.
Per million tokens. Prices and uptime via OpenRouter, checked 13 Oct 2026.
Both are developed by OpenAI but target different use cases. GPT-4o (Omni) has a 128K token context window vs GPT-5.1's 400K. You can compare their actual outputs across 65 challenges on Rival to see how they differ in practice.
It depends on your use case. GPT-4o (Omni) and GPT-5.1 each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 65 challenges so you can judge which fits your needs best.
GPT-4o (Omni) costs $2.5/M input tokens and GPT-5.1 costs $1.25/M input tokens. GPT-5.1 is $1.25/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.
This page shows a side-by-side comparison of GPT-4o (Omni) and GPT-5.1 across shared challenges. You can vote on which model produced the better output in a blind duel. Browsing and voting are free. No account is needed to look; signing in only saves your votes and likes.