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. DeepSeek V4 FlashvsGPT-6 Luna Pro
Updated Sep 2026

DeepSeek V4 FlashvsGPT-6 Luna Pro

GPT-6 Luna Pro is cheaper than DeepSeek V4 Flash at $0.1/M vs $0.14/M input tokens.

DeepSeek V4 Flash and GPT-6 Luna Pro compared across 20 shared prompts
SpecDeepSeek V4 FlashGPT-6 Luna Pro
Input price$0.14/M tokens$0.1/M tokens
Output price$0.28/M tokens$0.5/M tokens
Context window1.0M tokens1.1M tokens
WeightsOpenClosed
Free API (OpenRouter)NoNo
ReleasedApr 2026Sep 2026
Side by side

Same prompt, both answers

Opening lines from 6 of the 20 prompts both answered. Formatting stripped, words untouched.

Advanced Longevity Plan (Biohacker)

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

DeepSeek V4 Flash665 words
This is a Biohacker’s Longevity Protocol, designed for a 90-day optimization cycle. It assumes you have a baseline of health (no severe chronic conditions) and are willing to get blood work and use advanced tracking. Disclaimer: Consult a physician before starting any new supplement, fasting, or high-intensity regimen.
Read the full answer
GPT-6 Luna Pro2,057 words
12-week longevity and performance plan This is a structured starting plan for a generally healthy adult—not a diagnosis or a substitute for medical care. The best longevity interventions are still the unglamorous ones: not smoking, regular exercise, adequate sleep, a high-quality diet, healthy blood pressure and…
Read the full answer

Beginner's Longevity Plan

Outline a simple, actionable 1-month plan for someone starting their journey towards better health and longevity. Focus on 3 key areas…

DeepSeek V4 Flash967 words
This is a fantastic goal. The key for a beginner is consistency over intensity. Trying to overhaul your entire life overnight is a recipe for burnout. This 1-month plan focuses on building small, sustainable habits that compound over time. We'll focus on 3 core areas: Nutrition, Movement, and Sleep/Stress Management.
Read the full answer
GPT-6 Luna Pro327 words
A simple 1-month plan for better health and longevity Choose three foundations: eating well, moving regularly, and sleeping consistently. Aim for steady habits, not perfection. Diet: Make nourishing choices easier Week 1: Add one serving of fruit or vegetables to one meal each day.
Read the full answer

Debug This Architecture

Here's the architecture for a real-time collaborative document editor (like Google Docs): **System Overview:** - Frontend: React SPA with…

DeepSeek V4 Flash1,942 words
Failure Modes, Race Conditions, and Scaling Bottlenecks The described architecture has several critical flaws that compromise reliability, consistency, and scalability. Below is a systematic analysis with proposed solutions and their trade-offs.
Read the full answer
GPT-6 Luna Pro1,906 words
The main architectural risk is that this design treats collaborative editing as ordinary “last write wins” data storage. It is not: edits need a well-defined order, reliable propagation, and a conflict model that preserves concurrent work.
Read the full answer

Mini LBO Underwrite

You are underwriting a 5-year LBO for a private equity investment committee. Company (fictional): HarborTech Services (HTS) –…

DeepSeek V4 Flash442 words
LBO Model: HarborTech Services (HTS) – Base Case & Sensitivity Year-by-Year Financial Projections (FY2026–FY2030) ($ millions) FY2026 FY2027 FY2028 FY2029 FY2030 Revenue 972.00 1,040.04 1,102.44 1,157.56 1,215.44 EBITDA 136.08 156.01 176.39 191.00 206.63 Less: Cash Interest (64.80) (63.08) (60.08) (55.69) (50.16) –…
Read the full answer
GPT-6 Luna Pro434 words
Operating and debt schedule Conventions: Interest is calculated on beginning-of-year debt; the 1% Term Loan amortization is 1% of its original $480m principal ($4.8m annually). Mezzanine PIK accrues at 2% annually.
Read the full answer

Michelin Star Recipe Design

Design an innovative recipe for a multi-component dish worthy of a Michelin 3-star restaurant. The recipe should feature an unusual…

DeepSeek V4 Flash1,455 words
Here is a conceptual recipe for a three-Michelin-star-level dish that deconstructs a classic pairing into something utterly unexpected, using advanced techniques and a narrative of geological wonder.
Read the full answer
GPT-6 Luna Pro1,215 words
Turbot, Sea Buckthorn, Mussel Beurre Blanc, and Celery-Root Silk Serves 4 A composed main course built around an unusual but harmonious pairing: briny mussel and turbot with intensely tart, apricot-like sea buckthorn.
Read the full answer

Adversarial Contract Review

Here is a contract for a software consulting engagement: --- SOFTWARE CONSULTING AGREEMENT This Agreement is entered into between TechCorp…

DeepSeek V4 Flash1,977 words
Below is an analysis of each problematic clause in the Software Consulting Agreement, explaining why it is exploitative, suggesting specific modifications to protect the contractor, and providing the legal reasoning behind those changes.
Read the full answer
GPT-6 Luna Pro2,116 words
This agreement is heavily one-sided. Several terms let the Client expand the work, delay or deny payment, claim ownership of the Contractor’s existing materials, and expose the Contractor to potentially unlimited liability.
Read the full answer
Our Verdict
DeepSeek V4 Flash
DeepSeek V4 Flash
GPT-6 Luna Pro
GPT-6 Luna Pro

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

Too close to call

Reviewing agent-written code?See a Brief PR report

API pricing

Cost per 1M tokens

DeepSeek V4 Flash
Input
$0.14
Output
$0.28
1.8× cheaper
GPT-6 Luna Pro
Input
$0.10
1.4× cheaper
Output
$0.50

GPT-6 Luna Pro wins input (1.4× cheaper)·DeepSeek V4 Flash wins output (1.8× cheaper)

Where to run it

18 hosts, cheapest first

DeepSeek V4 Flash16 hosts
HostInOutContextUptime
RRelacefp4$0.03 in·$1.28 out·1M·99.9% upBaidu Qianfanfp8$0.05 in·$0.10 out·1M·99.7% upSStreamLakefp8$0.05 in·$0.10 out·1M·97% upDDeepInfrafp8$0.09 in·$0.18 out·1M·99.5% upGGMI Cloudfp8$0.09 in·$0.18 out·1M·99.8% upVVenice$0.10 in·$0.19 out·1M·99.3% up
10 more hostsFewer hosts
DDigitalOcean$0.10 in·$0.20 out·1M·100% upSSiliconFlowfp8$0.13 in·$0.28 out·1M·98.1% upAlibaba Cloudfp8$0.13 in·$0.27 out·1M·99.1% upAAtlasCloudfp4$0.14 in·$0.28 out·1M·98.9% upNNovitafp8$0.14 in·$0.28 out·1M·100% upPParasailfp8$0.14 in·$0.28 out·1M·99.7% upOOpenInferencefp8$0.14 in·$0.70 out·1M·98.7% upNNextBitfp8$0.15 in·$0.30 out·1M·99.9% upMMancerfp8$0.19 in·$0.50 out·1M·98.8% upAzure AI Foundrydegraded$0.21 in·$0.56 out·1M·91.4% up
GPT-6 Luna Pro2 hosts
HostInOutContextUptime
Azure AI Foundry$0.10 in·$0.50 out·1.1M·98.6% upOpenAI$0.10 in·$0.50 out·1.1M·99.9% up

Per million tokens. Prices and uptime via OpenRouter, checked 25 Sep 2026.

Research

What we learned reading every model

FAQ

Common questions

DeepSeek V4 Flash is developed by DeepSeek while GPT-6 Luna Pro is developed by OpenAI. DeepSeek V4 Flash has a 1.0M token context window vs GPT-6 Luna Pro's 1.1M. You can compare their actual outputs across 20 challenges on Rival to see how they differ in practice.

It depends on your use case. DeepSeek V4 Flash and GPT-6 Luna Pro each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 20 challenges so you can judge which fits your needs best.

DeepSeek V4 Flash costs $0.14/M input tokens and GPT-6 Luna Pro costs $0.1/M input tokens. GPT-6 Luna Pro is $0.04/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 DeepSeek V4 Flash and GPT-6 Luna Pro 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

DeepSeek V4 Flash logoSolar Mini 4 logo
DeepSeek V4 Flash vs Solar Mini 4Landed Sep 2026
GPT-6 Luna Pro logoQwen3.8 Max Prime logo
GPT-6 Luna Pro vs Qwen3.8 Max PrimeLanded Sep 2026
DeepSeek V4 Flash logoGLM 5.3 Prime logo
DeepSeek V4 Flash vs GLM 5.3 PrimeLanded Sep 2026
GPT-6 Luna Pro logoQwen3.8 Omni Flash logo
GPT-6 Luna Pro vs Qwen3.8 Omni FlashLanded Sep 2026
DeepSeek V4 Flash logoCommand A+ logo
DeepSeek V4 Flash vs Command A+Landed Sep 2026
GPT-6 Luna Pro logoClaude Opus 5.5 logo
GPT-6 Luna Pro vs Claude Opus 5.5Landed Sep 2026
DeepSeek V4 Flash logoGPT-6 Sol Pro logo
DeepSeek V4 Flash vs GPT-6 Sol ProLanded Sep 2026
GPT-6 Luna Pro logoGPT-6 Luna logo
GPT-6 Luna Pro vs GPT-6 LunaLanded Sep 2026

Same lab, same size, long tail

DeepSeek V4 Flash logoDeepSeek V4 Flash Vision Exp logo
DeepSeek V4 Flash vs DeepSeek V4 Flash Vision ExpSame lab
DeepSeek V4 Flash logoDeepSeek V4.1 Flash logo
DeepSeek V4 Flash vs DeepSeek V4.1 FlashSame lab
GPT-6 Luna Pro logoGPT-6 Sol Pro logo
GPT-6 Luna Pro vs GPT-6 Sol ProSame lab
GPT-6 Luna Pro logoGPT-6 Sol logo
GPT-6 Luna Pro vs GPT-6 SolSame lab
DeepSeek V4 Flash logoMercury logo
DeepSeek V4 Flash vs MercuryNew provider
DeepSeek V4 Flash logoMercury 2 logo
DeepSeek V4 Flash vs Mercury 2New provider
DeepSeek V4 Flash logoMercury 2.5 logo
DeepSeek V4 Flash vs Mercury 2.5Same size
DeepSeek V4 Flash logoMercury 2.5 Preview logo
DeepSeek V4 Flash vs Mercury 2.5 PreviewNew provider

Model pages

DeepSeek V4 Flash logo
DeepSeek V4 Flash58 outputs, specs and price
GPT-6 Luna Pro logo
GPT-6 Luna Pro20 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