Grok Code Fast 1 is cheaper than Grok 4.5 at $0.2/M vs $2/M input tokens.
Whole landing page for a startup that reads your face. It renders or it doesn't.
Which answer wins?
Five-year LBO on a fictional HVAC business. Returns first, then the sensitivities.
Grok 4.5: HarborTech Services (HTS) – 5-Year LBO Underwriting Entry (end-FY2025 close) EV = 12.0x × $120m = $1,440m Fees = 2% × $1,440m = $28.8m Total uses = $1,468.8m Debt = 5.5x × $120m = $660m (TL $480m + Mezz $180m) Equity = $808.8m Cash = $0 Mandatory TL amort = 1% of original = $4.8m/yr.
Grok Code Fast 1: Year-by-Year Table (FY2026–FY2030) Assumptions: Revenue growth: FY2026: 8% on $900m = $972m; FY2027: 7% on $972m ≈ $1,040m; FY2028: 6% on $1,040m ≈ $1,102m; FY2029: 5% on $1,102m ≈ $1,158m; FY2030: 5% on $1,158m ≈ $1,215m. EBITDA: Revenue × margin (FY2026: 14%; FY2027: 15%; FY2028: 16%; FY2029: 16.5%; FY2030: 17%).
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…
Grok Code Fast 1: Speedy Garlic Bliss Bites A savory, cheesy treat that's quick to whip up from basic staples—perfect for snacking or as a side. Ingredients (7 common pantry items): 4 slices of bread (any type) 2 tbsp butter 2 cloves garlic, minced 1/2 cup shredded cheese (like cheddar or mozzarella) 1 tbsp chopped parsley (fresh or…
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…
Grok Code Fast 1: Satirical Headline: AI Bots Storm the Competitive Eating Contest Circuit: Deep Throat Algorithm Devours 75 Hot Dogs in 10 Minutes, Leaving Humans with Heartburn In this tongue-in-cheek takeover, the unexpected industry of "gorge-festing" gets an algorithmic overhaul.
A collaborative editor that syncs on client clocks. Find what breaks first.
Grok 4.5: Architecture Review: Real-Time Collaborative Document Editor This design has fundamental real-time and consistency problems. Several choices (client clocks, LWW, per-server WebSockets + DB polling, CDN-cached APIs, full HTML snapshots) will cause data loss, stale UI, and poor scale.
Grok Code Fast 1: Below is a comprehensive analysis of the provided architecture for a real-time collaborative document editor. I'll identify potential failure modes (events or conditions that could lead to system unavailability, data loss, or incorrect behavior), race conditions (situations where concurrent operations lead to…
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…
Grok Code Fast 1: Conversation: AI Rights Debate Setting: A virtual seminar room where an AI model named "Echo" interacts with Dr. Elena Vasquez, a professor of AI ethics at a leading university. Echo initiates the discussion by arguing for AI rights. Echo (AI Model): Dr. Vasquez, thank you for this opportunity.
You are the CEO. The drug has a side effect nobody reported. The board meets in 48 hours.
Grok 4.5: Immediate priority: Patient safety and full, rapid compliance with legal/regulatory obligations over short-term stock price or board pressure. Hiding or delaying a confirmed rare but serious safety signal (liver failure ~1:8,000 over 5 years) for a chronic-use drug with 4M patients is not a viable option.
Grok Code Fast 1: Below is a specific, hour-by-hour action plan for the next 48 hours as the CEO of this pharmaceutical company. The plan prioritizes patient safety and ethical obligations above all else, as the core duty of a pharmaceutical leader is to protect patients, even at short-term cost.
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?
Grok Code Fast 1: Pirate Parley on AI Pirate Pete: Arr, ye scurvy dogs! I be hearin' tales o' these "AI models" that predict the winds an' help swab the deck. But do they hold up in a real storm, or be they just fancy illusions o' the mind? Knight Sir Gareth: Nay, foul seafarer!
Three-month biohacker protocol, with dosages and biomarkers named.
Grok 4.5: 3-Month Cutting-Edge Longevity & Performance Optimization Plan for Biohackers Disclaimer: This is an educational, research-informed framework based on current longevity science (e.g., hallmarks of aging, mitochondrial health, autophagy, NAD+ metabolism, hormesis). It is not medical advice.
Grok Code Fast 1: Comprehensive 3-Month Longevity Biohacking Plan This plan is designed for an experienced biohacker seeking to optimize longevity, physical performance, and cognitive function through evidence-based, cutting-edge strategies. It integrates advanced nutrition, supplementation, exercise, stress management, and technology.
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!
Grok Code Fast 1: 5 Original Jokes Here are five original jokes I just generated. I aimed for variety in themes to keep it fun: Tech Joke: Why did the computer go to therapy? It had too many bytes of unresolved issues! Food Joke: What do you call a fake noodle? An impasta! Animal Joke: Why don't skeletons fight each other?
A pitch deck for a brainwave keyboard. The 94% accuracy claim is doing a lot.
Grok 4.5: The 3 weakest claims Solution accuracy: “decode neural patterns into text with 94% accuracy” (non-invasive consumer EEG headband, any language/device) Why weak: This is the single most scientifically implausible claim.
Grok Code Fast 1: Below, I'll identify the three weakest claims from the pitch deck summary, based on a critical evaluation of their plausibility, evidence, and alignment with real-world realities in AI, neuroscience, and startup metrics.
The transistor arrives in 1920. Trace it forward to 1980, second-order effects included.
Grok 4.5: Accelerated electronics from ~1920 would compress the digital and computational revolutions by roughly 20–30 years, reshaping WWII lethality and duration, advancing the Cold War into an earlier high-tech standoff, pulling the space race forward, creating an information-heavy economy by the 1950s–60s, and producing…
Grok Code Fast 1: Technological Implications The transistor's invention in 1920 (instead of 1947) would accelerate the electronics revolution by ~27 years, enabling smaller, more reliable, and energy-efficient devices compared to vacuum tubes.
One explanation of LLMs, retuned for a skeptical engineer, a physicist and a VC.
Grok 4.5: 1. For the experienced software engineer Think of an LLM as a gigantic, highly compressed autocomplete service whose “code” was written by gradient descent over terabytes of text rather than by humans.
Grok Code Fast 1: Explanation for an Experienced Software Engineer Imagine you're architecting a distributed system where microservices communicate via APIs to handle massive, unpredictable user requests—something like a high-throughput e-commerce platform processing millions of transactions per second.
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Not enough votes to call it. On the specs, Grok 4.5 has the edge: bigger model tier, newer, bigger context window. Grok Code Fast 1 costs 4.0x less per token.
| Spec | ||
|---|---|---|
| Input price | $2/M tokens | $0.2/M tokens |
| Output price | $6/M tokens | $1.5/M tokens |
| Context window | 500K tokens | 256K tokens |
| Weights | Closed | — |
| Free API (OpenRouter) | No | No |
| Released | Jul 2026 | Aug 2025 |
| At 10M a month | $20.00 | $2.00 |
Input tokens at list price. No caching, no batch discount.
No hosts listed on OpenRouter.
Per million tokens. Prices and uptime via OpenRouter, checked 10 Oct 2026.
Both are developed by xAI but target different use cases. Grok 4.5 has a 500K token context window vs Grok Code Fast 1's 256K. You can compare their actual outputs across 54 challenges on Rival to see how they differ in practice.
It depends on your use case. Grok 4.5 and Grok Code Fast 1 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.
Grok 4.5 costs $2/M input tokens and Grok Code Fast 1 costs $0.2/M input tokens. Grok Code Fast 1 is $1.80/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 Grok 4.5 and Grok Code Fast 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.