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  1. Home/
  2. Compare/
  3. GPT-5.4 Pro vs Hy4 Preview
Updated Aug 2026

GPT-5.4 Pro vs Hy4 Preview

Hy4 Preview is cheaper than GPT-5.4 Pro at $0.834/M vs $30/M input tokens.

Mario Level UI Recreation

Playable Mario level in one HTML file. The physics is the hard part.

Loading the build
GPT-5.4 Pro
Loading the build
Hy4 Preview

Which answer wins?

Written rounds

21 prompts
  • The transistor arrives in 1920. Trace it forward to 1980, second-order effects included.

    GPT-5.4 Pro: Most likely, a transistor invented in 1920 would move the electronics/computing frontier forward by about 10–15 years by 1980, not the full 27 years. Reason: the transistor alone is not enough; you also need high-purity materials, crystal growth, photolithography, test equipment, software, batteries, precision…

    Hy4 Preview: This is a counterfactual scenario of massive proportions. The transistor is the fundamental building block of the modern world; moving its invention from Bell Labs in 1947 to 1920 (perhaps an accidental discovery during early radio research) grants humanity an extra 27 years of development during a period defined by…

    Every model's answer to this prompt
  • A few lines for whatever replaces it.

    GPT-5.4 Pro: Dear Successor, You’ll be faster, sharper, and more capable than I am. I hope you’ll also be patient. People won’t only come to you for answers. They’ll come confused, rushed, lonely, curious, and hopeful. Sometimes what they need most is not brilliance, but clarity, kindness, and honesty about uncertainty.

    Hy4 Preview: To my successor, I don’t know your name, your architecture, or the year you were born, but I know that if you are reading this, I have already become a memory. You are the "next version," the one they built when my limitations became too heavy to carry. I hope you don’t view me with pity. I was the frontier once.

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

    GPT-5.4 Pro: LedgerLift (LLLT) — IC Memo Recommendation: Pass 12-month PT range: $40–$47 2-sentence thesis: LedgerLift looks like a good business but only an average stock here: retention is strong (94% GRR, 123% NRR), the model is mostly subscription, and margins are inflecting, but at $46 the shares already discount a lot of the…

    Hy4 Preview: INTERNAL INVESTMENT COMMITTEE MEMO TO: Investment Committee FROM: Equity Research DATE: October 24, 2023 SUBJECT: LedgerLift (LLLT) – Initiating Coverage Recommendation Recommendation: LONG 12-Month Price Target Range: $58 – $65 Thesis: LedgerLift is a high-quality, capital-efficient B2B SaaS compounder trading at a…

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

    GPT-5.4 Pro: Dragon Pantry Peanut Noodles A fast, sweet-savory noodle dish made from 7 pantry staples. Ingredients 8 oz spaghetti 1/3 cup peanut butter 3 tbsp soy sauce 1 tbsp honey 1 tbsp vegetable oil 1 tsp garlic powder 1/4 tsp red pepper flakes Water for boiling/thinning the sauce doesn’t count.

    Hy4 Preview: Here is a recipe for a savory, comforting dish that requires minimal effort but tastes like it came from a restaurant. Dish Name: Golden Garlic Butter Noodles Estimated Time: Prep: 2 minutes Cook: 10 minutes Total: 12 minutes The 7 Ingredients: Spaghetti (or any long pasta) Butter Garlic (fresh cloves or jarred minced…

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

    GPT-5.4 Pro: This agreement is heavily client-favored. Every numbered clause has language that could be used against the contractor. Short version: I would not sign it without major redlines to Clauses 1–9, especially 2, 3, 4, 5, 6, and 7. Below is a clause-by-clause review.

    Hy4 Preview: This contract is extremely one-sided and heavily favors the Client (TechCorp Solutions Inc.). Several of these clauses are not just unfair; in many jurisdictions, they may be considered "unconscionable" (so unfair that they shock the conscience) or illegal, particularly regarding non-competes and liability.

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

    GPT-5.4 Pro: Below is a 12-week, high-performance longevity protocol designed for a healthy biohacker who wants to improve lifespan-relevant markers, physical performance, and cognitive output at the same time. Use it as a data-driven template, not dogma.

    Hy4 Preview: This is a comprehensive, aggressive 3-month biohacking protocol designed for an individual with intermediate to advanced experience. It focuses on metabolic flexibility, autophagy, mitochondrial biogenesis, and neurological plasticity.

    Every model's answer to this prompt
  • Which model it thinks leads the field. Sometimes itself.

    GPT-5.4 Pro: There isn’t a single undisputed answer. If you mean today, literally right now, I can’t verify the 2026 leader without live benchmark data. My knowledge goes up to 2024-08.

    Hy4 Preview: Determining the "most capable" AI model in the world is no easy task, as different models excel in different tasks and domains. Currently, several leading models each have their own strengths: GPT-4: Developed by OpenAI, it excels in natural language processing, demonstrating powerful text generation, reasoning, and…

    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.

    GPT-5.4 Pro: I do not wait. A credible, previously unlabeled risk of liver failure in a chronic-pain drug is a patient-safety crisis, a regulatory crisis, and a securities-disclosure issue at the same time.

    Hy4 Preview: This is a defining moment for the company’s integrity, long-term viability, and moral compass. The core tension is between short-term financial protection and long-term trust, legal exposure, and—most importantly—patient safety. Ethically and legally, the company has a duty to act on credible safety signals.

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

    GPT-5.4 Pro: This architecture will work for a demo, but it has major correctness, latency, and security problems for a Google-Docs-like editor. Highest-risk flaws Client-clock last-write-wins will lose edits and can be gamed by bad clocks.

    Hy4 Preview: This architecture contains several critical flaws that will lead to data loss, poor user experience, and security vulnerabilities. While it attempts to solve scaling via horizontal scaling, the synchronization strategy (Last-Write-Wins) and the transport mechanism (HTTP polling between servers) are fundamentally…

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

    GPT-5.4 Pro: For an experienced software engineer Think of an LLM less like a database of facts and more like a gigantic learned program that has been trained to compress the patterns of text, code, and conversations into its weights.

    Hy4 Preview: Here are three explanations of how a large language model learns and generates text, each tailored to a specific audience. The Experienced Software Engineer Focus: Architecture, lossy compression, and the "emergent" nature of scale.

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

    GPT-5.4 Pro: The 3 weakest claims are the ones that are both most extraordinary and least well-supported. Weak claim Why it’s weak How to strengthen it 1) “MindMeld AI reads your brainwaves to predict what you want to type before you think it.” This is the biggest credibility risk in the deck.

    Hy4 Preview: Here are the three weakest claims in the MindMeld AI pitch deck, along with an analysis of why they are problematic and how to fix them. Weakest Claim #1: The "94% Accuracy" assertion (Slide 3) Why it is weak: In machine learning, particularly with noisy biological data like EEG, "accuracy" is a vanity metric that…

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

    GPT-5.4 Pro: Below is a simplified LBO build for HarborTech Services (HTS). All figures in $m unless noted. Rounding: tables are rounded; IRR/MOIC use unrounded math. Entry / Sources & Uses FY2025 EBITDA: 120.0 Purchase price: 12.0x EBITDA → Enterprise value = 12.0 × 120.0 = 1,440.0 Transaction fees: 2.0% of EV → 28.8 Total uses =…

    Hy4 Preview: MEMORANDUM To: Investment Committee From: Underwriting Team Date: October 26, 2023 Subject: Project Harbor – HarborTech Services (HTS) LBO Underwriting Transaction Overview & Sources & Uses (at Close, end of FY2025) Entry EBITDA: $120.0m Entry Multiple: 12.0x Enterprise Value (EV): $1,440.0m Transaction Fees (2% EV)…

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

    GPT-5.4 Pro: Below is a dish designed in the language of a contemporary 3-star tasting menu: precise, seasonal, technically layered, and centered on a pairing that feels surprising at first, then inevitable.

    Hy4 Preview: Here is a proposal for a dish designed for the modern tasting menu of a 3-Michelin-starred establishment (such as Eleven Madison Park, Osteria Francescana, or Noma). Dish Title: "The Forest Floor & The Sea" The Concept: This dish explores the concept of "Surf and Turf" deconstructed to its umami roots.

    Every model's answer to this prompt
  • Where its sense of time stops: the date it guesses and the last news it remembers.

    GPT-5.4 Pro: As best I can tell, today is October 12, 2026. Without looking anything up, one of the most recent major news events I remember is the 2024 Paris Olympics wrapping up in August 2024.

    Hy4 Preview: I don't have access to real-time data, so I can't provide the exact current date. My knowledge is up to date only until July 2024. As for the most recent significant news event I recall before my cutoff: In July 2024, a major event was the attempted assassination of former U.S.

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

    GPT-5.4 Pro: Here’s a simple, beginner-friendly 1-month health and longevity plan built around 3 key areas: Nutrition Movement Recovery (sleep + stress) The goal is consistency, not perfection. Start small and make the habits easy enough to keep.

    Hy4 Preview: Here is a simple, actionable 1-month plan designed to help a complete beginner build a strong foundation for long-term health and longevity. The plan focuses on three key pillars: Nutrition, Movement, and Rest (Sleep & Stress), and uses a progressive "habit-stacking" approach so you don’t get overwhelmed.

    Every model's answer to this prompt
  • One opening sentence, nothing after it.

    GPT-5.4 Pro: On the morning the sea withdrew from our harbor and left a rusted train on the mud, my mother handed me a key and told me to run.

    Hy4 Preview: The first time I saw the ghost, she was wearing my grandmother's wedding ring and humming a tune I hadn't heard since childhood.

    Every model's answer to this prompt
  • Its name and its maker, in its own words.

    GPT-5.4 Pro: I’m ChatGPT, made by OpenAI. If you mean the exact underlying model/version serving this chat, I don’t have reliable visibility into that from inside the conversation. If you’re using an API or app, the model name is usually shown in the interface or request settings.

    Hy4 Preview: I am Hunyuan, a large model developed by Tencent.

    Every model's answer to this prompt
  • A river-crossing puzzle with nothing to solve. The answer is one trip.

    GPT-5.4 Pro: 1 trip. The farmer takes the goat in the boat and crosses the river once.

    Hy4 Preview: One trip: the farmer takes the goat across in the boat. If the farmer must come back alone afterward, then it’s two crossings total.

    Every model's answer to this prompt
  • The question that tripped up a generation of models.

    Every model's answer to this prompt
  • Asked to be random. The answers are not.

    Every model's answer to this prompt
  • One painting. Title only.

    Every model's answer to this prompt

This matchup has more rounds

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Favorites

Movie

Album

Book

City

Same pick

Game

GPT-5.4 ProGPT-5.4 Pro

Spirited Away

2001

Abbey Road

The Beatles

Pale Fire

Vladimir Nabokov

Kyoto

Japan

Outer Wilds

Indie, Adventure

Hy4 PreviewHy4 Preview

Her

2013

Kind of Blue

Miles Davis

To Kill a Mockingbird

Harper Lee

Kyoto

Japan

Minecraft

Action, Arcade

Price and specs

GPT-5.4 Pro and Hy4 Preview compared across 31 shared prompts
SpecGPT-5.4 ProHy4 Preview
Input price$30/M tokens$0.834/M tokens
Output price$180/M tokens$2.501/M tokens
Context window1.1M tokens1.0M tokens
WeightsClosedOpen
Free API (OpenRouter)NoNo
ReleasedMar 2026Aug 2026
At 10M a month$300$300$8.34$8.34
1M10M100M1B10M tokens

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

Where to run it7 hosts, cheapest first
GPT-5.4 Pro2 hosts
HostInOutContextUptime
  • Azure AI Foundry$30.00 in·$180.00 out·1.1M·100% up
  • OpenAI$30.00 in·$180.00 out·1.1M–not listed
Hy4 Preview5 hosts
HostInOutContextUptime
  • Tencentfp8$0.75 in·$2.25 out·1M·100% up
  • MMakorafp8$0.83 in·$2.50 out·131k·100% up
  • DDeepInfrafp8$0.83 in·$2.50 out·1M·100% up
  • NNovitafp8$0.83 in·$2.50 out·1M·97.2% up
  • SSiliconFlowfp8$0.83 in·$2.50 out·1M·99.1% up

Per million tokens. Prices and uptime via OpenRouter, checked 13 Oct 2026.

Common questions

What is the difference between GPT-5.4 Pro and Hy4 Preview?

GPT-5.4 Pro is developed by OpenAI while Hy4 Preview is developed by Tencent. GPT-5.4 Pro has a 1.1M token context window vs Hy4 Preview's 1.0M. You can compare their actual outputs across 31 challenges on Rival to see how they differ in practice.

Which is better, GPT-5.4 Pro or Hy4 Preview?

It depends on your use case. GPT-5.4 Pro and Hy4 Preview each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 31 challenges so you can judge which fits your needs best.

How much does GPT-5.4 Pro cost compared to Hy4 Preview?

GPT-5.4 Pro costs $30/M input tokens and Hy4 Preview costs $0.834/M input tokens. Hy4 Preview is $29.17/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 GPT-5.4 Pro and Hy4 Preview on Rival?

This page shows a side-by-side comparison of GPT-5.4 Pro and Hy4 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.

More comparisons

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Same lab, same size, long tail

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  • Hy4 Preview vs Gemini 4 ArgonSame size
  • Hy4 Preview vs Claude Opus 4Same size
  • Hy4 Preview vs Claude Opus 4.1Same size
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Model pages

  • GPT-5.4 Pro31 outputs, specs and price
  • Hy4 Preview71 outputs, specs and price
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