Model comparison
GPT-5.6 Luna vs Qwen 3.8 27B
OpenAI against Qwen, compared on context, price, and verified benchmark results.
Catalog record checked September 26, 2026Individual provider fields may changeEvidence confidence: High — see receipts below
OpenAI
GPT-5.6 Luna
Budget
Qwen
Qwen 3.8 27B
Budget · Open weights
| Specification | GPT-5.6 Luna | Qwen 3.8 27B |
|---|---|---|
| Provider | ||
| Provider | OpenAI | Qwen |
| Tier | ||
| Tier | Budget | Budget |
| Context window | ||
| Context window | Winner: 1.05M | 262K |
| Max output | ||
| Max output | 128K | Not verifiedUnverified |
| Input / 1M tokens | ||
| Input / 1M tokens | Winner: $0.20 | $0.50 |
| Output / 1M tokens | ||
| Output / 1M tokens | Winner: $1.20 | $3 |
| Weights | ||
| Weights | Closed | Open |
| Parameters | ||
| Parameters | previous-generation GPT-5.6 small tier | 27B dense VLM (Gated DeltaNet hybrid) |
| Reasoning levels | ||
| Reasoning levels | none, low, medium, high, xhigh, max | low, medium, xhigh |
| Modalities | ||
| Modalities | text, image | text, image, video |
| License | ||
| License | Not disclosedUnverified | Apache 2.0 |
| API model id | ||
| API model id | gpt-5.6-luna | qwen3.8-27b |
| Released | ||
| Released | July 9, 2026 | August 13, 2026 |
| Artificial Analysis Intelligence Index [max] (2026-09-26) | ||
| Artificial Analysis Intelligence Index [max] (2026-09-26) | 37.3 | Not verifiedUnverified |
| Artificial Analysis Intelligence Index [xhigh] (2026-09-26) | ||
| Artificial Analysis Intelligence Index [xhigh] (2026-09-26) | Not verifiedUnverified | 33.7 |
| SWE-bench Verified (2026-09-01) | ||
| SWE-bench Verified (2026-09-01) | 93 | Not verifiedUnverified |
| Terminal-Bench 2.1 (2026-07-09) | ||
| Terminal-Bench 2.1 (2026-07-09) | 84.7 | Not verifiedUnverified |
| LiveBench (2026-09-05) | ||
| LiveBench (2026-09-05) | 73.6 | Not verifiedUnverified |
Prices are USD per million tokens at standard rates, excluding batch and caching discounts. Bold indicates the better figure where one is objectively better. Values we could not confirm from the provider are shown as “Not verified” rather than estimated.
Benchmark receipts
Where each score comes from, and how far it can be compared across models.
- 2026-09-26Artificial Analysis
Composite index blending reasoning, knowledge, and coding evals into one 0–100 score.
Comparable with caveatOnly same-version scores are comparable. v4.3.2 was rebaselined (the top score fell from 66 on v4.1.1 to ~58), so v4.1.1 figures must not be compared with v4.3.2 figures — check measuredAt.
- 2026-09-05LiveBench official leaderboard (benchmark-owned), max effort
Contamination-resistant general capability across reasoning, coding, math, data analysis, and language, with monthly question refreshes.
Comparable with caveatRolling question set: observations months apart measure different question mixes. Record the measurement date and compare within ~1 month windows.
- 2026-09-01vals.ai SWE-bench Verified leaderboard (independent, mini-swe-agent bash-only) (independent; OpenAI did not report SWE-bench Verified for the GPT-5.6 family)
Real GitHub issue resolution: does the model's patch pass the hidden tests.
Comparable with caveatPost-audit vendor claims and pre-audit scores sit on different task trust levels; scaffolding (agent harness, compute budget) also dominates results. Never aggregate across scaffolds.
- 2026-07-09OpenAI GPT-5.6 announcement (vendor; chart transcribed by Vellum)
Agentic terminal work: multi-step tasks executed in a sandboxed shell environment.
Comparable with caveatNot comparable with Terminal-Bench 3.0 or 4.0 (different task sets) or v1; harness configuration (container, time limits) also shifts results.
Pricing tiers
GPT-5.6 Luna: Launch list was $1/$6; cut to $0.20/$1.20 on 2026-07-30. Above 272K input the whole request bills 2x input / 1.5x output. Cached input $0.02/MTok; cache writes 1.25x input; batch $0.10/$0.60.
Qwen 3.8 27B: Hosted qwen3.8-27b lists $0.50/$3.00 per MTok on Alibaba Cloud Model Studio (API launched 2026-08-19). Open weights (Apache 2.0) for self-hosting.
GPT-5.6 Luna
GPT-5.6 Luna was OpenAI's cheapest GPT-5.6 tier; GPT-6 Luna replaced it on 2026-09-22 at half the price ($0.10/$0.50).
Best for
- Classification
- High-volume chat
- Latency-sensitive pipelines
Watch out
Superseded by GPT-6 Luna, which costs half as much and matches it on the Artificial Analysis index; still served, not deprecated.
Qwen 3.8 27B
Qwen 3.8 27B is Alibaba's compact deployment-friendly dense VLM — 262K native context (1M via YaRN), Apache 2.0 weights, distinct from the hosted Qwen 3.8 Max API.
Best for
- Self-hosting on a single node
- Multimodal input at small scale
- Long-context on modest hardware
Watch out
Dense 27B means higher memory per token than an MoE of equal active size; video input is multimodal-input only.
When the cheaper one wins
GPT-5.6 Luna is cheaper on output at $1.20 per million tokens against $3 for Qwen 3.8 27B — about 2.5×. Use the cheaper tier for classification, extraction, summarisation, and any task where the expensive model’s extra score does not change the accepted output. The expensive one only pays if your hardest task actually fails on the cheap tier. These are standard-tier API rates, excluding batch and cache discounts.
Run the model pickerEvidence confidence: High
How strong and complete the evidence behind this comparison is — not a prediction of which model is better.
- Pricing verified on both sides — Input and output rates are verified for both models.
- 4/5 core specs verified on both sides — Not published for at least one side: max output.
- 1 shared named benchmark with differing scores — Measured on: Artificial Analysis Intelligence Index.
- Verified within the last 90 days — Newest catalog check was 2 days ago.
- Both models carry source citations — Each side has at least two catalog sources on record.
Source receipts
Each catalog figure was checked against the provider or an independent second source on the date shown.
- GPT-5.6 Luna: OpenAI — GPT-5.6 (accessed 2026-08-29)
- GPT-5.6 Luna: OpenAI API pricing (gpt-5.6-luna $0.20/$1.20) (accessed 2026-08-29)
- GPT-5.6 Luna: OpenAI — Introducing GPT-6 Sol and Luna (GPT-5.6 Luna successor) (accessed 2026-09-26)
- Qwen 3.8 27B: HuggingFace — Qwen3.8-27B model card (accessed 2026-08-29)
- Qwen 3.8 27B: LiveBench Leaderboard (Qwen 3.8 27B row) (accessed 2026-08-29)
- Qwen 3.8 27B: Alibaba Cloud Model Studio pricing (qwen3.8-27b $0.50/$3.00) (accessed 2026-09-26)
Related comparisons
- Claude Haiku 4.5 vs GPT-5.6 Luna
- Claude Haiku 4.5 vs Qwen 3.8 27B
- Claude Opus 5 vs GPT-5.6 Luna
- DeepSeek V3.1 vs GPT-5.6 Luna
- DeepSeek V3.1 vs Qwen 3.8 27B
- DeepSeek V4 Flash vs GPT-5.6 Luna
Diving deeper on one model? GPT-5.6 Luna · Qwen 3.8 27B
Common questions
GPT-5.6 Luna vs Qwen 3.8 27B
Answered from the verified figures on this page rather than general guidance.
Is GPT-5.6 Luna or Qwen 3.8 27B cheaper for input?
Is GPT-5.6 Luna or Qwen 3.8 27B cheaper for output?
Which has the larger context window, GPT-5.6 Luna or Qwen 3.8 27B?
Do GPT-5.6 Luna and Qwen 3.8 27B support the same reasoning levels?
Should I use GPT-5.6 Luna or Qwen 3.8 27B?
Can I self-host GPT-5.6 Luna or Qwen 3.8 27B?
Next step
Choosing between them
The verified figures that separate this pair, computed from the catalog rather than restated boilerplate.
- Input price: GPT-5.6 Luna costs $0.20 per 1M tokens versus $0.50 for Qwen 3.8 27B — a 2.5x difference at the headline tier.
- Context: GPT-5.6 Luna takes 1.05M against 262K for Qwen 3.8 27B — only decisive if your prompts approach the smaller window.
- Measured capability: GPT-5.6 Luna leads Artificial Analysis Intelligence Index 37.3 to 33.7 (measured 2026-09-26).
- Deployment: Qwen 3.8 27B publishes weights you can self-host; the other is API-only.
Choosing a harness rather than a model — Cursor, Copilot, Claude Code, Windsurf, or Lovable? Compare agentic harnesses · Latest releases.