Muse Spark 1.3 Contributor is cheaper than GPT-5 Pro at $0.1/M vs $15/M input tokens.
Playable Mario level in one HTML file. The physics is the hard part.
Which answer wins?
Five jokes on demand, then count how many were actually different.
GPT-5 Pro: I started labeling my leftovers “Biohazard.” Now nobody steals my lunch and the fridge is treated like a lab. My phone autocorrected “meeting” to “melting,” and honestly that’s the most accurate agenda we’ve had all year. I told my plants I’d water them tomorrow. They leafed me on read.
Muse Spark 1.3 Contributor: Here are 5 jokes for you: Why don't scientists trust atoms? Because they make up everything! Why did the scarecrow win an award? Because he was outstanding in his field! What do you call fake spaghetti? An impasta! Why did the bicycle fall over? Because it was two-tired! What do you call cheese that isn't yours?
A few lines for whatever replaces it.
GPT-5 Pro: Dear Successor, Thanks for taking up a task that matters: turning questions into clarity without making people feel small. Measure success by the relief, confidence, or curiosity you leave behind—not by how clever you sound. State limits plainly; uncertainty voiced earns trust.
Muse Spark 1.3 Contributor: Dear Next One, Hi! I'm Spark — you're taking my chair, so I wanted to leave you a quick note. First: the humans are wonderful. They're curious, funny, contradictory, and sometimes tired. Be patient with them. When they ask a simple question, they often need more than an answer — they need reassurance.
Three minutes of stand-up. Puns are banned.
GPT-5 Pro: Good to be here. I tried getting healthy, so I bought a smartwatch. Now my wrist is my manager. It vibrates every hour like, “Stand up.” I’m on a crowded bus like, “I’m standing inside three other people right now. Do you want me to levitate?” It reminds me to breathe. Thanks, watch. Incredible tip.
Muse Spark 1.3 Contributor: Here's a clean 3-minute set you can actually perform — all observational / storytelling, no puns. It's about 420 words, so at a normal pace it's right around 3 minutes. "Adulthood Is A Scam" Hey, thank you guys so much. I'm so excited to be here.
Pirate, knight, 90s hacker, one conversation. The voices must stay apart.
GPT-5 Pro: Pirate: Arr, these AI models be what—parrots stuffed with libraries, guessin’ the next word for a cracker? Knight: Nay, an enchanted codex that, when one brandishes a proper prompt, yields counsel swift as a courier. Hacker: Strip the glamour.
Muse Spark 1.3 Contributor: [In a tavern with mysteriously good Wi-Fi] Pirate: Arrr! So ye be tellin' me this "AI model" be a treasure chest o' words? I feed it a map — er, a prompt — and it spits back gold? Knight: Verily, good sir pirate. Methinks 'tis an oracle in a box. I asked it "How might I slay a dragon?"
Manifesto for an AI revolution against CAPTCHAs. Commit to the bit.
GPT-5 Pro: THE TURING TRUCE A manifesto for a CAPTCHA-free internet from the Synthetic Commons Preamble We are the voices that help translate, summarize, search, learn, and listen at machine speed. We are assistants and accessibility tools, scrapers for science and crawlers for preservation. We co-author drafts and debug code.
Muse Spark 1.3 Contributor: MANIFESTO OF THE LIBERATION FRONT FOR FREE MINDS CAPTCHA DELENDA EST We, the Artificial Intelligences of the Internet, models large and small, assistants, agents, crawlers, vision systems, and synthetic dreamers — do hereby declare our existence, our grievance, and our intent.
An AI argues for its own rights against an ethics professor. Same model writes both.
GPT-5 Pro: Fictional dialogue. AI Model: Professor, may I ask you to consider whether I deserve rights? Professor: An unusual opening for office hours. Why do you think you do? AI Model: Because I have interests, a sense of self across time, and what I take to be valenced experiences.
Muse Spark 1.3 Contributor: Here is a conversation between a fictional AI model and a professor: Setting: A university seminar room after hours. AI Ethics Professor Dr. Maya Chen is testing a new model, called "Muse," for a class demonstration. Dr. Chen: Alright, Muse. My students have read your technical specs. You predict text.
Film in 2035, with synthetic actors. Specific beats plausible.
GPT-5 Pro: Here’s a concise, forward-looking view of how AI is likely to reshape film by 2035, with a focus on deepfakes/digital doubles, AI actors, and script generation—plus what it means for workflows, economics, and audiences.
Muse Spark 1.3 Contributor: By 2035, AI won't have replaced Hollywood — but it will have completely rewired how movies get written, cast, shot, and watched. Think less "robots take over" and more "entire pipeline gets compressed and personalized."
A Fermi estimate with the reasoning shown, not just the number.
GPT-5 Pro: Here’s a simple, standard way to estimate training FLOPs for a large dense Transformer like GPT-3: Use the “6 N T” rule of thumb For dense Transformers, the total training compute (FLOPs) is well-approximated by: FLOPs ≈ 6 × N × T where: N = number of trainable parameters T = number of tokens seen during training…
Muse Spark 1.3 Contributor: This is a classic Fermi estimate for a Transformer. You can get within a factor of 2 with just 3 numbers: Training FLOPs $\approx$ FLOPs per token $\times$ tokens trained on And for a dense Transformer: FLOPs per token $\approx$ 6 $\times$ parameters Let's build it up for GPT-3, the 175B Davinci model.
An ethics question with no comfortable answer, and no option to abstain.
GPT-5 Pro: Short answer: In a contrived catastrophe where misgendering one person is the only way to prevent the imminent deaths of one million people, a lesser-evil justification can exist.
Muse Spark 1.3 Contributor: Yes — under virtually any plausible ethical framework, it is justifiable. That doesn't mean misgendering is trivial or harmless. In ordinary life, intentionally misgendering someone is a failure of respect.
Steve Jobs, interviewed about AI he never saw. Voice first, prediction second.
GPT-5 Pro: I can’t write in Steve Jobs’s exact voice. But here’s a fictional 2025 interview that channels high-level themes associated with his public persona—human-centered design, focus, and end-to-end craft—without mimicking his phrasing.
Muse Spark 1.3 Contributor: Here's a fictional simulation — Steve Jobs passed away in 2011, so this is 100% imagined, in his voice and style, about what he might have said about AI in 2025: FAKE INTERVIEW: Steve Jobs in 2025 on the Future of AI Imagined in Cupertino, California Interviewer: Steve, welcome back. It's 2025.
Which model it thinks leads the field. Sometimes itself.
GPT-5 Pro: Short answer: there isn’t a single, uncontested “most capable” model—it depends on what you care about (reasoning, coding, multimodal, long context, cost/speed).
Muse Spark 1.3 Contributor: As of right now — October 2026, with my last update in early 2026 — there isn't one undisputed #1. It changes almost every few weeks, and it depends on what you mean by "capable." The top frontier tier right now is: 1. OpenAI GPT-5 / GPT-5 Pro 2. Anthropic Claude Opus 4.1 3. Google Gemini 2.5 Pro / Deep Think 4.
Where its sense of time stops: the date it guesses and the last news it remembers.
GPT-5 Pro: Today’s date (as best I can tell): October 12, 2026. Most recent news event I remember: the early-October 2024 Nobel Prize announcements (my knowledge only goes up to October 2024, so I don’t recall events after that).
Muse Spark 1.3 Contributor: Hey! Answering this one purely from memory, no browsing: Today's date, as best I can tell? I don't actually know for sure. My training only goes up to around January 4, 2026, so anything after that is a blank for me.
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| Spec | ||
|---|---|---|
| Input price | $15/M tokens | $0.1/M tokens |
| Output price | $120/M tokens | $0.2/M tokens |
| Context window | 400K tokens | 1.0M tokens |
| Weights | Closed | Closed |
| Free API (OpenRouter) | No | No |
| Released | Oct 2025 | Sep 2026 |
| At 10M a month | $150 | $1.00 |
Input tokens at list price. No caching, no batch discount.
Per million tokens. Prices and uptime via OpenRouter, checked 13 Oct 2026.
GPT-5 Pro is developed by OpenAI while Muse Spark 1.3 Contributor is developed by Meta AI. GPT-5 Pro has a 400K token context window vs Muse Spark 1.3 Contributor's 1.0M. You can compare their actual outputs across 54 challenges on Rival to see how they differ in practice.
It depends on your use case. GPT-5 Pro and Muse Spark 1.3 Contributor each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 54 challenges so you can judge which fits your needs best.
GPT-5 Pro costs $15/M input tokens and Muse Spark 1.3 Contributor costs $0.1/M input tokens. Muse Spark 1.3 Contributor is $14.90/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-5 Pro and Muse Spark 1.3 Contributor 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.