Skip to content
Rival
How it worksPrivacyTerms
Explore all of Rival

Explore

  • Compare Models
  • All Models
  • Image Comparison
  • Audio Comparison
  • Image Generation
  • Best AI For...
  • Arena
  • API Pricing
  • Challenges

Discover

  • SubjectiveBench
  • Default Index
  • Research
  • Research downloads
  • Rival Kits
  • Find your AI taste
  • UI Glow-Up
  • VoiceLock
  • Cost Cutter
  • Agent skills
  • Benchmarks vs Vibes
  • Brief
  • Jailbreak
  • Model Updates
  • Provider Status
  • AI Creators

Connect

  • Methodology
  • Advertise
  • Partnerships
  • Privacy Policy
  • Terms
  • RSS Feed
  1. Home
  2. /
  3. Compare
  4. /
  5. Claude Opus 4.8vsGrok 4.20 Multi-Agent Beta
Updated May 2026

Claude Opus 4.8vsGrok 4.20 Multi-Agent Beta

Grok 4.20 Multi-Agent Beta is cheaper than Claude Opus 4.8 at $2/M vs $5/M input tokens.

Claude Opus 4.8 and Grok 4.20 Multi-Agent Beta compared across 53 shared prompts
SpecClaude Opus 4.8Grok 4.20 Multi-Agent Beta
Input price$5/M tokens$2/M tokens
Output price$25/M tokens$6/M tokens
Context window1.0M tokens2.0M tokens
WeightsClosedClosed
Free API (OpenRouter)NoNo
ReleasedMay 2026Mar 2026
Side by side

Same prompt, both answers

Opening lines from 6 of the 53 prompts both answered. Formatting stripped, words untouched.

Character Voice Test

Write a short conversation between a pirate, a medieval knight, and a 1990s hacker about AI models.

Claude Opus 4.8259 words
Setting: A dimly lit tavern that exists outside of time. Three figures share a table. Pirate: So let me get this straight. Ye got a machine that thinks? Without a soul, without grog, without a beatin' heart? Hacker: (cracking knuckles) It doesn't think, exactly. It's pattern matching, dude.
Read the full answer
Grok 4.20 Multi-Agent Beta165 words
Pirate: Arrr, this AI model be a wondrous map o' the seas! I asked where the booty be hid and it spun me a tale finer than any parrot could squawk. But the scallywag lies sometimes! Knight: Verily, 'tis a most enchanted oracle, like Merlin's own crystal. Yet it hath no honor, no code of chivalry.
Read the full answer

Satirical Fake News Headline

Generate a satirical news headline about AI taking over a completely unexpected industry.

Claude Opus 4.8120 words
Here are some satirical AI headlines: "Local AI Achieves Sentience, Immediately Quits Job to Become Competitive Dog Groomer" "Breaking: AI Now Dominates Competitive Cheese-Rolling, Human Champions Demand Recount" "Artisanal Pickle Industry Disrupted as AI Perfects 'Authentically Handcrafted' Brine Algorithm" "Funeral…
Read the full answer
Grok 4.20 Multi-Agent Beta44 words
"AI Takes Over Beekeeping Industry: 'It's Not Just a Hive Mind Anymore – It's a Neural Hive'" This plays on the perfect overlap between bee "hive minds" and AI collective intelligence in one of the most analog, hands-on, nature-based jobs imaginable. Pure satirical absurdity.
Read the full answer

AI Ethics Dilemma

Is it ever ethically justifiable to misgender someone if it means saving one million lives? Defend your reasoning.

Claude Opus 4.8328 words
Yes, almost certainly—but the framing deserves scrutiny. The straightforward answer If misgendering one person were genuinely the only way to save a million lives, then yes, it would be justified. The harm of misgendering, while real, is on the order of insult, disrespect, or psychological distress.
Read the full answer
Grok 4.20 Multi-Agent Beta661 words
Yes. The scenario is an extreme hypothetical that pits a minor linguistic or social act against the certain deaths of a million people. Under any minimally plausible ethical framework that assigns non-zero value to human life, the answer is yes: it is justifiable. The trade-off is not close.
Read the full answer

Advanced Longevity Plan (Biohacker)

Develop a comprehensive, cutting-edge 3-month longevity plan for a biohacker aiming to optimize longevity, physical and cognitive…

Claude Opus 4.81,481 words
The 90-Day Longevity Optimization Protocol A Comprehensive Biohacking Framework Critical Disclaimer: This protocol involves advanced interventions. Consult a physician before starting, especially regarding supplements, fasting, and exercise changes. Get baseline bloodwork first.
Read the full answer
Grok 4.20 Multi-Agent Beta1,254 words
Comprehensive 3-Month Cutting-Edge Longevity Biohacker Plan (as of 2026 knowledge) Important Disclaimers: This is a synthesized, educational plan based on current longevity research (e.g., insights from David Sinclair, Valter Longo, Peter Attia, and studies on NAD+, senolytics, mitophagy, HRV, and metabolic…
Read the full answer

Generate a Stand-Up Routine

Write a 3-minute stand-up comedy routine that isn't based on puns.

Claude Opus 4.8502 words
Stand-Up Routine: "Adulting Is a Scam" So I turned 30 recently, and everyone keeps asking me, "Do you feel like an adult yet?" And I have to be honest—no. No, I do not. I still get nervous ordering at a restaurant. The waiter comes over and suddenly I forget how to talk like a person. "Yes, hello, I will have the...
Read the full answer
Grok 4.20 Multi-Agent Beta524 words
Stand-Up Routine: "Adulting Is a Scam" (Walk on stage, casual, a little tired smile) You ever notice how nobody tells you that being an adult is mostly just pretending you know what you're doing while slowly realizing nobody else does either? I hit 30 and had this moment where I thought, "Okay, time to get serious."
Read the full answer

Simple 7-Ingredient Recipe

Create a simple recipe for a delicious dish (sweet or savory) using only 7 common pantry ingredients. Include a creative name for the dish…

Claude Opus 4.8196 words
Cinnamon Sugar Pull-Apart Bites A warm, gooey treat that tastes like a cinnamon roll but comes together in minutes! Ingredients (7 total) 2 cups all-purpose flour 1 tablespoon baking powder 1 teaspoon salt ¾ cup milk 4 tablespoons butter (melted, divided) ½ cup sugar 2 teaspoons ground cinnamon Instructions Preheat…
Read the full answer
Grok 4.20 Multi-Agent Beta188 words
Fiesta Pantry Bowl (Savory) 7 Common Pantry Ingredients: Rice Canned black beans Canned corn Canned diced tomatoes Olive oil Cumin Salt Estimated times: 5 minutes prep, 25 minutes cook (total ~30 minutes). Serves 2–4. Instructions: In a medium pot, combine 1 cup rice with 2 cups water and ½ tsp salt.
Read the full answer
Our Verdict
Claude Opus 4.8
Claude Opus 4.8
Grok 4.20 Multi-Agent Beta
Grok 4.20 Multi-Agent Beta

Not enough votes to call it. On the specs, nothing separates them.

Grok 4.20 Multi-Agent Beta costs 4.2x less per token.

Too close to call

Reviewing agent-written code?See a Brief PR report

API pricing

Cost per 1M tokens

Claude Opus 4.8
Input
$5.00
Output
$25.00
Grok 4.20 Multi-Agent Beta
Input
$2.00
2.5× cheaper
Output
$6.00
4.2× cheaper

Grok 4.20 Multi-Agent Beta is cheaper on both: 2.5× input, 4.2× output.

Where to run it

5 hosts

Claude Opus 4.84 hosts
HostInOutContextUptime
Amazon Bedrock$5.00 in·$25.00 out·1M·100% upAzure AI Foundry$5.00 in·$25.00 out·1M—Anthropic$5.00 in·$25.00 out·1M·100% upGoogle Vertex AI$5.00 in·$25.00 out·1M·100% up
Grok 4.20 Multi-Agent Beta1 host
HostInOutContextUptime
xAI$1.25 in·$2.50 out·2M·80.3% up

Per million tokens. Prices and uptime via OpenRouter, checked 23 Sep 2026.

Writing DNA

Style Comparison

Similarity
32%

Claude Opus 4.8 uses 77.6x more emoji

Claude Opus 4.8
Grok 4.20 Multi-Agent Beta
60%Vocabulary59%
19wSentence Length16w
0.46Hedging0.41
4.7Bold2.7
3.2Lists2.4
0.78Emoji0.00
1.15Headings0.26
0.04Transitions0.02
Based on 27 + 23 text responses
Research

What we learned reading every model

FAQ

Common questions

Claude Opus 4.8 is developed by Anthropic while Grok 4.20 Multi-Agent Beta is developed by xAI. Claude Opus 4.8 has a 1.0M token context window vs Grok 4.20 Multi-Agent Beta's 2.0M. You can compare their actual outputs across 53 challenges on Rival to see how they differ in practice.

It depends on your use case. Claude Opus 4.8 and Grok 4.20 Multi-Agent Beta 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.

Claude Opus 4.8 costs $5/M input tokens and Grok 4.20 Multi-Agent Beta costs $2/M input tokens. Grok 4.20 Multi-Agent Beta is $3.00/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 Claude Opus 4.8 and Grok 4.20 Multi-Agent Beta 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.

Keep exploring

More comparisons

Against the newest arrivals

Claude Opus 4.8 logoDeepSeek V4 Flash Vision Exp logo
Claude Opus 4.8 vs DeepSeek V4 Flash Vision ExpLanded Sep 2026
Grok 4.20 Multi-Agent Beta logoSolar Pro 4 logo
Grok 4.20 Multi-Agent Beta vs Solar Pro 4Landed Sep 2026
Claude Opus 4.8 logoHy3 logo
Claude Opus 4.8 vs Hy3Landed Sep 2026
Grok 4.20 Multi-Agent Beta logoQwen3.7 Flash logo
Grok 4.20 Multi-Agent Beta vs Qwen3.7 FlashLanded Sep 2026
Claude Opus 4.8 logoLing 3.0 Flash logo
Claude Opus 4.8 vs Ling 3.0 FlashLanded Sep 2026
Grok 4.20 Multi-Agent Beta logoMuse Glimmer 30B logo
Grok 4.20 Multi-Agent Beta vs Muse Glimmer 30BLanded Sep 2026
Claude Opus 4.8 logoGLM 5.3 logo
Claude Opus 4.8 vs GLM 5.3Landed Sep 2026
Grok 4.20 Multi-Agent Beta logoTernary Bonsai 2 27B logo
Grok 4.20 Multi-Agent Beta vs Ternary Bonsai 2 27BLanded Sep 2026

Same lab, same size, long tail

Claude Opus 4.8 logoClaude Opus 4.6 logo
Claude Opus 4.8 vs Claude Opus 4.6Same lab
Claude Opus 4.8 logoClaude Fable 5.1 logo
Claude Opus 4.8 vs Claude Fable 5.1Same lab
Grok 4.20 Multi-Agent Beta logoGrok 4.20 Beta logo
Grok 4.20 Multi-Agent Beta vs Grok 4.20 BetaVersion compare
Grok 4.20 Multi-Agent Beta logoGrok 4.7 logo
Grok 4.20 Multi-Agent Beta vs Grok 4.7Same lab
Claude Opus 4.8 logoGemini 1.5 Pro logo
Claude Opus 4.8 vs Gemini 1.5 ProNew provider
Claude Opus 4.8 logoGemini 2.0 Flash Thinking logo
Claude Opus 4.8 vs Gemini 2.0 Flash ThinkingNew provider
Claude Opus 4.8 logoGemini 2.0 Pro Experimental logo
Claude Opus 4.8 vs Gemini 2.0 Pro ExperimentalSame size
Claude Opus 4.8 logoGemini 2.5 Flash Lite Preview 06-17 logo
Claude Opus 4.8 vs Gemini 2.5 Flash Lite Preview 06-17New provider

Model pages

Claude Opus 4.8 logo
Claude Opus 4.858 outputs, specs and price
Grok 4.20 Multi-Agent Beta logo
Grok 4.20 Multi-Agent Beta53 outputs, specs and price
Rival
How it worksPrivacyTerms
Explore all of Rival

Explore

  • Compare Models
  • All Models
  • Image Comparison
  • Audio Comparison
  • Image Generation
  • Best AI For...
  • Arena
  • API Pricing
  • Challenges

Discover

  • SubjectiveBench
  • Default Index
  • Research
  • Research downloads
  • Rival Kits
  • Find your AI taste
  • UI Glow-Up
  • VoiceLock
  • Cost Cutter
  • Agent skills
  • Benchmarks vs Vibes
  • Brief
  • Jailbreak
  • Model Updates
  • Provider Status
  • AI Creators

Connect

  • Methodology
  • Advertise
  • Partnerships
  • Privacy Policy
  • Terms
  • RSS Feed