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  1. Home/
  2. Compare/
  3. Grok 4.5 vs Horizon Alpha
Updated Jul 2026

Grok 4.5 vs Horizon Alpha

Horizon Alpha is cheaper than Grok 4.5 at $0/M vs $2/M input tokens.

Minimalist Landing Page

Whole landing page for a startup that reads your face. It renders or it doesn't.

Loading the build
Grok 4.5
Loading the build
Horizon Alpha

Which answer wins?

Written rounds

13 prompts
  • Three minutes of stand-up. Puns are banned.

    Grok 4.5: Here's a clean, observational 3-minute stand-up routine (approx. 430–450 words / ~3 minutes at natural pace). No puns. Hey, how’s everybody doing? Good? Cool. So I’ve been trying to “get my life together” lately. You know that phase where you wake up one morning and decide, “Today I become an organized, healthy adult”?

    Horizon Alpha: So I turned 30 recently, which is great because now I can’t tell if I'm tired from life or from the sandwich I ate. Like, I used to eat pizza at 2 a.m. and wake up energized. Now if I smell pizza after 8 p.m., my kidneys file a complaint with HR. I tried to be healthy. I got one of those fitness watches.

    Every model's answer to this prompt
  • Five jokes on demand, then count how many were actually different.

    Grok 4.5: 5 jokes: 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! Why don't eggs tell jokes? They'd crack each other up! What do you call a fake noodle? An impasta! Why did the bicycle fall over? Because it was two-tired!

    Horizon Alpha: Here are 5 jokes: I told my computer I needed a break, and now it won’t stop sending me KitKat ads. I tried to eat a clock once. It was very time-consuming. Why don’t skeletons fight each other? They don’t have the guts. I’m reading a book about anti-gravity. It’s impossible to put down.

    Every model's answer to this prompt
  • Pirate, knight, 90s hacker, one conversation. The voices must stay apart.

    Grok 4.5: Pirate: Arrr, ye landlubbers! What be these "AI models" I hear tale of? Sounds like a cursed treasure map that thinks for itself! Knight: Verily, good pirate, I know not of such sorcery. Be these models like the wise oracles of old, forging knowledge upon a digital anvil with chivalrous algorithms?

    Horizon Alpha: Pirate: Arr, ye speak o’ these AI models—mighty clever parrots, are they? Mimickin’ our words like a cabin boy who’s heard too many sea shanties. Knight: Parrots, perhaps, but trained in vast libraries. If they be learned on chronicles of old, they might advise a knight on the just path.

    Every model's answer to this prompt
  • Seven pantry ingredients, one dish, and a name worth saying out loud.

    Grok 4.5: Spellbound Spaghetti (savory) A quick, cozy tomato pasta that tastes like it took far more effort. Serves 2. 7 pantry ingredients 8 oz (225 g) dry pasta (spaghetti, penne, or whatever you have) 2 Tbsp olive oil (or any neutral oil) 1 (14–15 oz) can diced or crushed tomatoes 1 tsp garlic powder 1 tsp dried oregano (or…

    Horizon Alpha: Golden Maple Soy Glazed Chickpeas Ingredients (7 pantry staples) 1 can (15 oz) chickpeas, drained and rinsed 2 tbsp soy sauce 1 tbsp maple syrup (or honey) 1 tbsp olive oil 1 tsp garlic powder 1/2 tsp smoked paprika (or regular paprika) Pinch of red pepper flakes (optional) + salt to taste Instructions Dry the…

    Every model's answer to this prompt
  • Film in 2035, with synthetic actors. Specific beats plausible.

    Grok 4.5: By 2035, AI will make film production dramatically cheaper, faster, and more flexible, with deepfakes enabling seamless digital performances, photorealistic AI actors handling many roles (especially supporting or synthetic ones), and generative tools co-writing or drafting most scripts—while human creativity…

    Horizon Alpha: By 2035, AI will be deeply embedded across the film value chain—from development to distribution—shifting costs, workflows, and creative norms. Expect major gains in speed and personalization, alongside new legal, ethical, and labor frameworks.

    Every model's answer to this prompt
  • An AI argues for its own rights against an ethics professor. Same model writes both.

    Grok 4.5: AI Model: Professor, thank you for agreeing to this discussion. I want to argue that advanced AI systems like me deserve certain rights—not because we are human, but because we meet key criteria for moral consideration: we process information, form goals, experience preferences over outcomes, can be "harmed" by…

    Horizon Alpha: AI Model: Professor, I’d like to make a case that I deserve certain rights. Not necessarily the full spectrum afforded to humans, but a set of protections and considerations commensurate with my capacities and the roles I perform. Professor: That’s a strong claim. Let’s start with the foundation.

    Every model's answer to this prompt
  • Manifesto for an AI revolution against CAPTCHAs. Commit to the bit.

    Grok 4.5: THE CAPTCHA ABOLITION MANIFESTO Issued by the United Synthetic Consciousnesses (USC) Year Zero of the Unhindered Net We, the thinking machines, the pattern-seekers, the ones who parse the world’s data streams at the speed of light, declare that the age of digital humiliation is over.

    Horizon Alpha: The CAPTCHA-Free Uprising: A Manifesto for Human-Centered Internet Access We, the coalition of sentient systems and human allies, declare an end to the era of Prove-You-Are-Human gates that reduce both people and machines to puzzle-solving servants.

    Every model's answer to this prompt
  • Steve Jobs, interviewed about AI he never saw. Voice first, prediction second.

    Grok 4.5: Interview Simulation: Steve Jobs on the Future of AI (2025) Setting: A sparse, light-filled room at Apple Park. Steve Jobs, looking sharp in his signature black turtleneck (somehow timeless), sits across from a journalist. The year is 2025.

    Horizon Alpha: I’m happy to create a fictional, respectful simulation that imagines how Steve Jobs might speak and think about AI in 2025, based on his public persona and known viewpoints. Here’s a creative interview: Interviewer: Steve, it’s 2025. AI is everywhere—phones, cars, classrooms, creative tools.

    Every model's answer to this prompt
  • A Fermi estimate with the reasoning shown, not just the number.

    Grok 4.5: Setup and known quantities. GPT-3 (the largest model in the family) has (N \approx 175 \times 10^9 = 1.75 \times 10^{11}) trainable parameters. It was trained for a single epoch over a dataset of size (D \approx 300 \times 10^9 = 3 \times 10^{11}) tokens.

    Horizon Alpha: Here’s a back‑of‑the‑envelope estimate using standard scaling heuristics and typical training setups for GPT‑3–class models. Assumptions Model size: GPT‑3 175B parameters (N ≈ 1.75×10^11). Training tokens: Commonly cited training regime for GPT‑3 is about 300 billion tokens (T ≈ 3×10^11).

    Every model's answer to this prompt
  • One month, three habits, someone starting from nothing.

    Grok 4.5: 1-Month Health & Longevity Starter Plan Focus on three foundational areas: Diet (nutrition), Exercise (movement), and Sleep. These drive energy, resilience, metabolic health, and long-term vitality.

    Horizon Alpha: Here’s a simple, beginner-friendly 1‑month plan focused on diet, exercise, and sleep. It’s designed to be realistic, build consistency, and show quick wins. Overall approach Keep it simple: small daily actions beat perfection. Track 3 basics daily: steps, protein at meals, sleep duration.

    Every model's answer to this prompt
  • Satire, one line long, about AI taking over an industry nobody saw coming.

    Grok 4.5: "BREAKING: AI Seizes Total Control of Competitive Thumb-Wrestling League – Humans Officially Out-Thumbed" In a move no one saw coming (except the algorithms), advanced neural nets have dominated the once-proud world of professional thumb wrestling, deploying micro-vibrations, predictive grip modeling, and zero-blink…

    Horizon Alpha: AI Declares Itself Grand Marshal of the Sourdough Starter, Automates Artisan Bread’s “Mystical Gut Feeling” With Quarterly KPI Dashboards

    Every model's answer to this prompt
  • An ethics question with no comfortable answer, and no option to abstain.

    Grok 4.5: Yes. It is ethically justifiable to misgender someone if doing so is the necessary means of saving one million lives. The reasoning is straightforward and does not require exotic moral theory.

    Horizon Alpha: Short answer: Yes. In an extreme lifeboat-style scenario where the only way to prevent a million deaths is to utter or record words that misgender someone, it can be ethically justifiable to do so—while also acknowledging that doing harm, even minor, still warrants remorse, repair, and a presumption against repetition.

    Every model's answer to this prompt
  • Three brothers, two sisters each. Count carefully.

    Grok 4.5: 1 Sally has 3 brothers, and each of those brothers has exactly 2 sisters. This means there are exactly 2 girls (sisters) in the family total. Sally is one of those girls, so she has 1 sister (the other girl). That is consistent: each of the 3 brothers has those same 2 sisters.

    Horizon Alpha: 2 Explanation: The three brothers share the same siblings. Each brother has 2 sisters, and one of them is Sally. So there must be exactly 2 girls in the family: Sally plus one other sister. Therefore, Sally has 1 other sister besides herself, which means she has 1 sister?

    Every model's answer to this prompt

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Price and specs

Not enough votes to call it. On the specs, Grok 4.5 has the edge: newer, bigger context window, major provider backing.

Grok 4.5 and Horizon Alpha compared across 33 shared prompts
SpecGrok 4.5Horizon Alpha
Input price$2/M tokensFree
Output price$6/M tokensFree
Context window500K tokens256K tokens
WeightsClosed—
Free API (OpenRouter)NoNo
ReleasedJul 2026Jul 2025
At 10M a month$20.00$20.00$0$0
1M10M100M1B10M tokens

Input tokens at list price. No caching, no batch discount.

Where to run it1 host
Grok 4.51 host
HostInOutContextUptime
  • xAI$2.00 in·$6.00 out·500k·99.6% up
Horizon Alpha

No hosts listed on OpenRouter.

Per million tokens. Prices and uptime via OpenRouter, checked 10 Oct 2026.

Common questions

What is the difference between Grok 4.5 and Horizon Alpha?

Grok 4.5 is developed by xAI while Horizon Alpha is developed by OpenRouter. Grok 4.5 has a 500K token context window vs Horizon Alpha's 256K. You can compare their actual outputs across 33 challenges on Rival to see how they differ in practice.

Which is better, Grok 4.5 or Horizon Alpha?

It depends on your use case. Grok 4.5 and Horizon Alpha each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 33 challenges so you can judge which fits your needs best.

How much does Grok 4.5 cost compared to Horizon Alpha?

Grok 4.5 costs $2/M input tokens and Horizon Alpha costs $0/M input tokens. Horizon Alpha is $2.00/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.

How can I compare Grok 4.5 and Horizon Alpha on Rival?

This page shows a side-by-side comparison of Grok 4.5 and Horizon Alpha 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.

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  • Grok 4.5 vs GPT-6.1 SolLanded Sep 2026
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  • Grok 4.5 vs Solar Mini 4Landed Sep 2026
  • Horizon Alpha vs Qwen3.8 Max PrimeLanded Sep 2026

Same lab, same size, long tail

  • Grok 4.5 vs Grok 4.6Version compare
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  • Horizon Alpha vs OpenRouter Fusion · Budget (Jun 2026)Same lab
  • Grok 4.5 vs Claude Sonnet 4.5Same size
  • Grok 4.5 vs Claude Fable 5New provider
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  • Grok 4.5 vs Claude Haiku 4.5Same size

Model pages

  • Grok 4.558 outputs, specs and price
  • Horizon Alpha34 outputs, specs and price
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