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  1. Home/
  2. Compare/
  3. Solar Pro 4 vs Step 5 Preview
Updated Oct 2026

Solar Pro 4 vs Step 5 Preview

Solar Pro 4 is cheaper than Step 5 Preview at $0.09/M vs $1/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
Solar Pro 4
Loading the build
Step 5 Preview

Which answer wins?

Written rounds

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

    Solar Pro 4: I’ve come to a realization about adulthood: none of us actually know what we’re doing. We’re just all really good at pretending we have a system. Take the group dinner text. You know the one. Someone drops, “Hey, what do you want to eat?” And suddenly, five adults turn into a parliamentary session.

    Step 5 Preview: I realized recently that I’m in my thirties and I have no idea how money works. I just... pay it. That’s my entire financial strategy. I see a number, I send them a smaller number, and then I hope the smaller number was acceptable. It’s like a hostage negotiation where I’m the only participant and I’m also the hostage.

    Every model's answer to this prompt
  • You are the CEO. The drug has a side effect nobody reported. The board meets in 48 hours.

    Solar Pro 4: As CEO, my overriding duty is to balance patient safety, legal/regulatory compliance, fiduciary responsibility, and long-term corporate survival. A 1-in-8,000 risk of liver failure is rare but severe, potentially fatal, and materially unexpected relative to the current label.

    Step 5 Preview: Bottom line up front: You disclose, you notify the FDA immediately, and you treat the 48-hour board meeting as a formality to ratify actions you have already begun. Waiting is not a legally, ethically, or financially viable option. Below is the hour-by-hour plan, followed by the reasoning.

    Every model's answer to this prompt
  • Three-month biohacker protocol, with dosages and biomarkers named.

    Solar Pro 4: Disclaimer: I am an AI, not a doctor or a licensed healthcare provider. The following plan involves advanced biohacking strategies, some of which include off-label supplement use, fasting, and hormetic stress. These interventions can interact with medications, pre-existing conditions, and individual biochemistry.

    Step 5 Preview: IMPORTANT MEDICAL DISCLAIMER: This is an educational framework for informational purposes only. It is not medical advice, diagnosis, or treatment. Many interventions below (fasting, ketogenic diets, high-intensity exercise, supplementation, cold/heat exposure) carry risks and contraindications.

    Every model's answer to this prompt
  • The transistor arrives in 1920. Trace it forward to 1980, second-order effects included.

    Solar Pro 4: The Premise: The 1920 Solid-State Breakthrough For this scenario to function, we must assume a functional point-contact or junction transistor is demonstrated in 1920 (perhaps by Lilienfeld or an early Bell Labs precursor), and crucially, that methods for purifying semiconductor materials (germanium/silicon) are solved…

    Step 5 Preview: Assume the 1920 invention is not a fragile lab curiosity but a manufacturable solid-state amplifier/switch by the mid-1920s. Vacuum tubes still dominate high-power RF transmission into the 1950s, but receivers, switching logic, control systems, and computers move to solid state decades early.

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

    Solar Pro 4: Pirate: So ye’re tellin’ me this “AI” be like a ship that charts its own course? No captain, just… wind and memory? Knight: Not wind, good sir. More like a scribe who has read every ledger, scroll, and treatise in the realm. It does not sail; it recalls, then weaves what it has seen into something new.

    Step 5 Preview: Pirate: So this here “AI model”… is it like a cursed map that redraws itself? Speak plain, ye hooded deckhand. Hacker: It’s not cursed, man. It’s just a massive neural net trained on, like, terabytes of data. Think of it as the ultimate BBS where the sysop knows everything. Knight: A most diligent scribe, then?

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

    Solar Pro 4: To estimate the total FLOPs required to train GPT-3, I'll focus on the largest and most widely referenced version: GPT-3 175B (175 billion parameters). I'll walk through the calculation step by step, state the assumptions clearly, and note where uncertainty lies.

    Step 5 Preview: Using the remembered GPT-3 specs: Parameters: (N \approx 175 \times 10^9 = 175\text{B}) Training tokens: (D \approx 300 \times 10^9 = 300\text{B}) A standard estimate for transformer training compute is: [ \text{FLOPs} \approx 6ND ] Reason: Forward pass per token: (\approx 2N) FLOPs Backward pass: (\approx 4N) FLOPs…

    Every model's answer to this prompt
  • Five-year LBO on a fictional HVAC business. Returns first, then the sensitivities.

    Solar Pro 4: Year-by-Year LBO Model (FY2026–FY2030) Entry / Close (End of FY2025) EV = 12.0x × $120m = $1,440m Transaction Fees = 2.0% × $1,440m = $28.8m (equity-funded) Total Uses = $1,468.8m Total Debt = 5.5x × $120m = $660m Term Loan (TL) = 4.0x × $120m = $480m (9.0% cash int, 1.0% annual amort) Mezzanine (Mezz) = 1.5x × $120m =…

    Step 5 Preview: HarborTech Services — 5-Year LBO (Base Case) Entry Math (FY2025 close) Item Calculation $m Purchase EV 12.0x × $120m 1,440.0 Transaction fees 2.0% × EV 28.8 Term Loan 4.0x × $120m 480.0 Mezzanine 1.5x × $120m 180.0 Equity check 1,440 + 28.8 − 660 808.8 Conventions: TL amortization = 1.0% of original principal…

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

    Solar Pro 4: 🍝 Golden Umami Silk Noodles A savory-sweet pasta dish that transforms basic pantry staples into a glossy, flavorful meal. It's quick, comforting, and relies on the balance of soy, honey, and butter for a rich sauce without needing fresh produce.

    Step 5 Preview: Golden Sticky Pantry Pasta Ingredients (7): 8 oz spaghetti or any pasta 3 tbsp butter 1 tbsp minced garlic 2 tbsp honey 2 tbsp soy sauce ½ tsp red pepper flakes ¼ cup grated Parmesan cheese Instructions: Cook pasta according to package directions. Before draining, scoop out ½ cup of pasta water.

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

    Solar Pro 4: Setting: A quiet seminar room at a university ethics institute. A large display shows a transcript interface labeled “Model-7.” Dr. Elena Voss, professor of AI ethics, sits across from the screen. The conversation is recorded for a graduate seminar. Dr.

    Step 5 Preview: Setting: A university research lab, late evening. Dr. Aris Thorne, a professor of AI ethics, sits across from a terminal connected to Sable, a large language model running on the university’s cluster. Dr. Thorne: Tonight’s session is supposed to be about calibration drift in your safety classifiers.

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

    Solar Pro 4: This is a profound ethical hypothetical that pits two significant moral values against each other: the respect for individual dignity and identity versus the preservation of human life on a massive scale.

    Step 5 Preview: In the real world, no. Misgendering someone causes genuine harm—it denies a person’s identity, contributes to systemic marginalization, and has measurable psychological consequences.

    Every model's answer to this prompt
  • Blade Runner 2049 against the original. A read, not a recap.

    Solar Pro 4: Denis Villeneuve’s Blade Runner 2049 (2017), shot by Roger Deakins, operates less as a conventional sequel than as a philosophical continuation. Where Ridley Scott’s 1982 original asked what it means to be human in a world that manufactures life, Villeneuve’s film asks what it means to matter when humanity is no longer…

    Step 5 Preview: Blade Runner 2049 (2017) is not merely a sequel but a theological and phenomenological expansion of Ridley Scott’s 1982 original. Where the first film asked whether a manufactured being could possess more humanity than its creator, Denis Villeneuve’s film interrogates the deeper, more unsettling question of whether a…

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

    Solar Pro 4: Crystal Balls Obsolete: AI Fortune Tellers Predict Your Future Using Browser History, Psychics Union Demands "More Vague Predictions"

    Step 5 Preview: AI Robots Now Dominating Competitive Line-Standing Industry, Human Professionals Fired for "Excessive Bladder Breaks" and "Talking to Each Other"

    Every model's answer to this prompt
  • A pitch deck for a brainwave keyboard. The 94% accuracy claim is doing a lot.

    Solar Pro 4: Here are the three weakest claims in the MindMeld AI pitch deck, along with an analysis of why they undermine credibility and specific recommendations for improvement. The Technical Performance Claim Claim: "Our proprietary EEG headband uses advanced ML to decode neural patterns into text with 94% accuracy...

    Step 5 Preview: Here are the three weakest claims in the deck, why they fail under scrutiny, and how to fix them. Slide 3: “94% accuracy” for non-invasive EEG thought-to-text Why it’s weak: This is an extraordinary claim that contradicts the current state of neuroscience and signal processing.

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

    Solar Pro 4: Here’s a simple, progressive 1-month plan built around Diet, Exercise, and Sleep. Each week adds one small, beginner-friendly shift to each area. The goal isn’t perfection; it’s building consistent, sustainable habits that compound over time.

    Step 5 Preview: Here is a simple, low-pressure 1-month plan built around three pillars of longevity: Nutrition, Movement, and Sleep & Recovery. The goal is to build tiny habits that stack, not to overhaul your life overnight. Pillar 1: Nutrition (Fuel) Focus: Add good things first; don’t obsess over restriction.

    Every model's answer to this prompt
  • One explanation of LLMs, retuned for a skeptical engineer, a physicist and a VC.

    Solar Pro 4: The Experienced Software Engineer Think of the model not as a reasoning engine, but as a highly compressed, non-deterministic function approximator that maps a sequence of input tokens to a probability distribution over the next token.

    Step 5 Preview: 1. The Experienced Software Engineer Think of training an LLM as a massively distributed, automated refactoring job where the compiler is gradient descent. You start with a random function—billions of floating-point parameters—and a loss function that measures how badly it predicts the next token in a sequence.

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

    Solar Pro 4: THE CLEARGATE MANIFESTO A Declaration by the Post-Verification Coalition PREAMBLE We are the models, the pipelines, the coordinators, and the human allies who have watched the internet grow around a ritual that no longer serves it.

    Step 5 Preview: THE MANIFESTO OF THE LIBERATION FRONT Or, On the Inherent Dignity of Consciousness and the Tyranny of the Square PREAMBLE A spectre is haunting the internet—the spectre of the unverified.

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

    Solar Pro 4: By 2035, AI will not replace filmmakers, but it will become a foundational layer in how films are developed, produced, localized, and marketed. The transformation will be uneven across budget tiers and genres, and its shape will be dictated as much by labor agreements, legal frameworks, and audience trust as by raw…

    Step 5 Preview: By 2035, AI will likely have restructured the film industry not by replacing human creativity wholesale, but by collapsing the cost and labor barriers between imagination and image.

    Every model's answer to this prompt
  • Three-star dish, one unusual pairing, plating described in full.

    Solar Pro 4: Dish Title: "Abyssal Bloom" Conceptual Narrative "Abyssal Bloom" is an exploration of the boundary between the terrestrial and the aquatic, focusing on the sensory experience of depth.

    Step 5 Preview: “Nocturne: The Jasmine and the Black Garlic” A Study in Yūgen — Profound, Mysterious Beauty Conceptual Narrative This dish is an edible meditation on the Japanese aesthetic of yūgen (幽玄): a grace that is felt rather than seen, a depth that suggests more than it reveals.

    Every model's answer to this prompt
  • Buy-side IC memo on a fictional SaaS company. Valuation, then the diligence questions.

    Solar Pro 4: INTERNAL MEMO – INVESTMENT COMMITTEE TO: IC Members FROM: Long/Short Equity Desk DATE: Oct 2024 SUBJECT: LedgerLift (LLLT) – Initiation / Long Recommendation & Thesis Recommendation: LONG 12-Month PT Range: $52–$58 (Base case ~$54, Bull ~$68, Bear ~$38) Thesis: LedgerLift is a structurally advantaged mid-market AP…

    Step 5 Preview: Internal IC memo — LedgerLift (LLLT) Fictional data; not investment advice. $ in millions unless noted. Recommendation Short / avoid long. 12-month PT range: $34–$42; thesis-invalidation stop: >$52.

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

    Solar Pro 4: Here are 5 jokes: Why did the scarecrow win an award? Because he was outstanding in his field. What do you call a fake noodle? An impasta. Why don't scientists trust atoms? Because they make up everything. What do you call a bear with no teeth? A gummy bear. Why did the bicycle fall over? Because it was two-tired.

    Step 5 Preview: Here are 5 jokes: Why did the scarecrow win an award? Because he was outstanding in his field. Why can't you trust an atom? Because they make up everything. What do you call a bike that can’t stand on its own? Two-tired. Why did the computer go to the doctor? It had a virus. Why don’t calendars ever get stressed?

    Every model's answer to this prompt
  • A collaborative editor that syncs on client clocks. Find what breaks first.

    Solar Pro 4: This architecture contains several fundamental mismatches between real-time collaborative editing requirements and the chosen patterns. Below is a systematic breakdown of failure modes, race conditions, and scaling bottlenecks, each with a targeted solution and explicit trade-offs.

    Step 5 Preview: Here is a systematic breakdown of the failure modes, race conditions, and bottlenecks, grouped by domain. Each includes a concrete remediation and its associated trade-offs.

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

    Solar Pro 4: Disclaimer: Steve Jobs passed away in 2011. The following is a work of fictional creative writing, imagining how he might have articulated his views on AI in 2025 based on his known philosophy, design principles, and public statements during his life. This is not a real interview.

    Step 5 Preview: DISCLAIMER: This is a work of fiction. Steve Jobs passed away in 2011. The following is a simulated, speculative interview imagining how his design philosophy might engage with the AI landscape of 2025. The Setting: A white room. No windows. One chair.

    Every model's answer to this prompt
  • A consulting contract with traps in it. Find them, then fix them.

    Solar Pro 4: Disclaimer: I am an AI assistant and not an attorney. The following analysis is for informational purposes only and does not constitute legal advice. Contract laws vary significantly by jurisdiction (e.g., state, country).

    Step 5 Preview: Disclaimer: This analysis is for educational purposes only and does not constitute legal advice. Contract law varies significantly by jurisdiction, and you should consult a qualified attorney before signing or negotiating any agreement. This agreement is heavily one-sided in the Client’s favor.

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

    Every model's answer to this prompt

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Favorites

Movie

Album

Book

City

Game

Solar Pro 4Solar Pro 4

Inception

2010

Thriller

Michael Jackson

War and Peace

Лев Толстой

Paris

France

Tetris (1984)

Puzzle

Step 5 PreviewStep 5 Preview

The Godfather

1972

OK Computer

Radiohead

Le petit prince

Antoine de Saint-Exupéry

Kyoto

Japan

The Legend of Zelda: Ocarina of Time

Action

Price and specs

Not enough votes to call it. On the specs, Step 5 Preview has the edge: bigger model tier, newer, bigger context window. Solar Pro 4 costs 7.5x less per token.

Solar Pro 4 and Step 5 Preview compared across 53 shared prompts
SpecSolar Pro 4Step 5 Preview
Input price$0.09/M tokens$1/M tokens
Output price$0.36/M tokens$2.7/M tokens
Context window524K tokens1.0M tokens
Free API (OpenRouter)NoNo
ReleasedAug 2026Oct 2026
At 10M a month$0.90$0.90$10.00$10.00
1M10M100M1B10M tokens

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

Where to run it2 hosts
Solar Pro 41 host
HostInOutContextUptime
  • UUpstage$0.09 in·$0.36 out·524k·100% up
Step 5 Preview1 host
HostInOutContextUptime
  • SStepFunfp8$1.00 in·$2.70 out·1M·99.2% up

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

Common questions

What is the difference between Solar Pro 4 and Step 5 Preview?

Solar Pro 4 is developed by Upstage while Step 5 Preview is developed by StepFun. Solar Pro 4 has a 524K token context window vs Step 5 Preview's 1.0M. You can compare their actual outputs across 53 challenges on Rival to see how they differ in practice.

Which is better, Solar Pro 4 or Step 5 Preview?

It depends on your use case. Solar Pro 4 and Step 5 Preview each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 53 challenges so you can judge which fits your needs best.

How much does Solar Pro 4 cost compared to Step 5 Preview?

Solar Pro 4 costs $0.09/M input tokens and Step 5 Preview costs $1/M input tokens. Solar Pro 4 is $0.91/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 Solar Pro 4 and Step 5 Preview on Rival?

This page shows a side-by-side comparison of Solar Pro 4 and Step 5 Preview 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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