GPT-6 Astra vs Mercury 2
GPT-6 Astra leads Mercury 2 on the Artificial Analysis Intelligence Index, 52.7 to 10.8, and Mercury 2 costs 66.7x less per output token ($0.75 vs $50.00 per million). Updated October 22, 2026; 39 benchmarks have a result for both.
vs boards won of 39 shared
GPT-6 Astra or Mercury 2: which to pick
Only GPT-6 Astra has a coding score, 85.1 on the Vibe Coding Index; Mercury 2 has none, so the two cannot be ranked on coding.
Pick Mercury 2 for output tokens 66.7x cheaper ($0.75 vs $50.00 per million).
Model AGPT-6 AstraOpenAI85.1/1005 independent benchmarksNo cost per solved taskModel BMercury 2InceptionNot benchmarked1 independent benchmarkNo cost per solved task
- Shared results
- 39
- GPT-6 Astra only
- 82
- Mercury 2 only
- 3
- Like-for-like categories
- 7 of 9
Only benchmarks that tested both models count toward a pick; a result only one model has is shown but not compared.
Which one for your work
Each card is decided by one number both models carry. Where only one has it, the card says so and makes no call.
Coding
Vibe Coding Index, six public coding benchmarks
No call
Only GPT-6 Astra has a coding score, so no call is made.
One side not measured
Intelligence
AA Intelligence Index
GPT-6 Astra
GPT-6 Astra leads, 52.7 against 10.8.
Same board, both measured
Agentic work
AA Agentic Index
GPT-6 Astra
GPT-6 Astra leads, 51.0 against 1.6.
Same board, both measured
Web design
Design Arena: websites
GPT-6 Astra
GPT-6 Astra leads, 1336 against 1035.
Same board, both measured
General
Vals Index
No call
Only GPT-6 Astra has a Vals Index result, 65.0%.
Directional only
Long documents
Listed context window
GPT-6 Astra
GPT-6 Astra takes 1.05M tokens against 128K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Mercury 2
GPT-6 Astra $0.035, Mercury 2 $0.0006 per turn.
List prices
At a glance
- Coding index
- GPT-6 Astra 85.1 from 5 benchmarks, Mercury 2 not benchmarked.
- Widest category
- Web design, 49.9 points apart on average over 8 shared benchmarks.
- Widest single gap
- LMArena WebDev: GPT-6 Astra 1774 against Mercury 2 1171, 82.0 points apart on a 0 to 100 scale.
- Output price
- GPT-6 Astra $50.00 against Mercury 2 $0.75 per million output tokens, 66.7x apart.
- Context window
- GPT-6 Astra takes 1.05M tokens, Mercury 2 128K.
Benchmark by benchmark
First the score: boards each model leads, per category, where both have a result. Then every board, a category to a fold; bars are each result on a 0 to 100 scale, so compare the two in a row, not one row with another.
| Category | GPT-6 Astra | Bars | Mercury 2 | Ties |
|---|---|---|---|---|
| Coding | 9 | 0 | ||
| Intelligence | 1 | 0 | ||
| Agentic work | 1 | 0 | ||
| Reasoning | 5 | 0 | ||
| Knowledge | 3 | 0 | ||
| Web design | 8 | 0 | ||
| General | 12 | 0 | ||
| All shared boards | 39 | 0 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index90
| Benchmark | GPT-6 Astra | Mercury 2 | Leader |
|---|---|---|---|
| LiveBench coding | 93.7% | Not measured | Only GPT-6 Astra measured |
| LMArena WebDev | 1774 | 1171 | GPT-6 Astra |
| AA Coding Index | 76.9 | 31.1 | GPT-6 Astra |
| Terminal-Bench 4 (Vals AI) | 59.6% | Not measured | Only GPT-6 Astra measured |
| Vibe Code Bench (Vals AI) | 89.6% | Not measured | Only GPT-6 Astra measured |
| Code migration (Vals AI) | 67.7% | Not measured | Only GPT-6 Astra measured |
| ProgramBench (Vals AI) | 5.5% | Not measured | Only GPT-6 Astra measured |
| IOI (Vals AI) | 100.0% | Not measured | Only GPT-6 Astra measured |
| Terminal-Bench 2.1 (Vals AI) | 87.3% | Not measured | Only GPT-6 Astra measured |
| SWE-bench Multimodal (Vals AI) | 43.3% | Not measured | Only GPT-6 Astra measured |
| Vibe Code Bench 1-100 (Vals AI) | 27.6% | Not measured | Only GPT-6 Astra measured |
| CyberBench (Vals AI) | 41.1% | Not measured | Only GPT-6 Astra measured |
| SciCode | 56.5% | 37.7% | GPT-6 Astra |
| Terminal-Bench Hard (Artificial Analysis run) | Not measured | 26.5% | Only Mercury 2 measured |
| FrontierCode | 53.3% | Not measured | Only GPT-6 Astra measured |
| FrontierSWE | 65.5% | Not measured | Only GPT-6 Astra measured |
| GSO-Bench | 79.4% | Not measured | Only GPT-6 Astra measured |
| WeirdML | 93.3% | 43.2% | GPT-6 Astra |
| MirrorCode | 46.7% | Not measured | Only GPT-6 Astra measured |
| ALE-Bench | 2951.3 | 785.6 | GPT-6 Astra |
| LMArena Text: coding | 1489 | 1390 | GPT-6 Astra |
| LMArena Text: software and IT | 1474 | 1385 | GPT-6 Astra |
| LMArena WebDev: React | 1798 | 1160 | GPT-6 Astra |
| LMArena WebDev: HTML | 1775 | 1199 | GPT-6 Astra |
| LMArena WebDev: from an image | 1726 | Not measured | Only GPT-6 Astra measured |
| SciCode | 12.3% | Not measured | Only GPT-6 Astra measured |
| Neither model has a result on the other 13 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | GPT-6 Astra | Mercury 2 | Leader |
|---|---|---|---|
| AA Intelligence Index | 52.7 | 10.8 | GPT-6 Astra |
| Epoch Capabilities Index | 168.8 | Not measured | Only GPT-6 Astra measured |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | GPT-6 Astra | Mercury 2 | Leader |
|---|---|---|---|
| AA Agentic Index | 51.0 | 1.6 | GPT-6 Astra |
| Design Arena: agents building web apps | 1374 | Not measured | Only GPT-6 Astra measured |
| Design Arena: agents building full-stack apps | 1357 | Not measured | Only GPT-6 Astra measured |
| Design Arena: agents building mobile apps | 1312 | Not measured | Only GPT-6 Astra measured |
| Design Arena: agents building Godot games | 1348 | Not measured | Only GPT-6 Astra measured |
| Design Arena: PowerPoint slides | 1219 | Not measured | Only GPT-6 Astra measured |
| Design Arena: spreadsheets | 1379 | Not measured | Only GPT-6 Astra measured |
| LiveBench research | 85.2% | Not measured | Only GPT-6 Astra measured |
| LiveBench browser | 84.0% | Not measured | Only GPT-6 Astra measured |
| LiveBench long agentic | 82.4% | Not measured | Only GPT-6 Astra measured |
| SREBench (Vals AI) | 56.9% | Not measured | Only GPT-6 Astra measured |
| Finance Agent (Vals AI) | 53.5% | Not measured | Only GPT-6 Astra measured |
| Tax Agent Bench (Vals AI) | 20.7% | Not measured | Only GPT-6 Astra measured |
| Legal Research Bench (Vals AI) | 39.4% | Not measured | Only GPT-6 Astra measured |
| Harvey's Legal Agent Benchmark (Vals AI) | 7.1% | Not measured | Only GPT-6 Astra measured |
| Excel Modeling Benchmark (Vals AI) | 71.7% | Not measured | Only GPT-6 Astra measured |
| BioMysteryBench (Vals AI) | 79.3% | Not measured | Only GPT-6 Astra measured |
| Terminal-Bench-Science (Vals AI) | 62.9% | Not measured | Only GPT-6 Astra measured |
| Vals Science Index | 65.1% | Not measured | Only GPT-6 Astra measured |
| Time Horizon Index (Vals AI) | 90.5% | Not measured | Only GPT-6 Astra measured |
| CUA-bench (Vals AI) | 19.2% | Not measured | Only GPT-6 Astra measured |
| Robo-bench (Vals AI) | 23.3% | Not measured | Only GPT-6 Astra measured |
| τ²-Bench Telecom | Not measured | 70.8% | Only Mercury 2 measured |
| APEX-Agents | 64.7% | Not measured | Only GPT-6 Astra measured |
| Remote Labor Index | 20.8% | Not measured | Only GPT-6 Astra measured |
| BALROG | 68.3% | Not measured | Only GPT-6 Astra measured |
| SpireClimb | 25.7% | Not measured | Only GPT-6 Astra measured |
| Vending-Bench 2 | $15,515 | Not measured | Only GPT-6 Astra measured |
| Neither model has a result on the other 13 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index50
| Benchmark | GPT-6 Astra | Mercury 2 | Leader |
|---|---|---|---|
| LiveBench reasoning | 92.7% | Not measured | Only GPT-6 Astra measured |
| MysteryMechanism (Vals AI) | 53.1% | Not measured | Only GPT-6 Astra measured |
| GPQA Diamond (Artificial Analysis run) | 96.3% | 77.0% | GPT-6 Astra |
| Humanity's Last Exam (Artificial Analysis run) | 54.7% | 17.1% | GPT-6 Astra |
| GPQA Diamond (Epoch AI run) | 95.8% | Not measured | Only GPT-6 Astra measured |
| ARC-AGI | 98.5% | Not measured | Only GPT-6 Astra measured |
| ARC-AGI-2 | 95.0% | Not measured | Only GPT-6 Astra measured |
| Chess puzzles | 74.0% | Not measured | Only GPT-6 Astra measured |
| Mystery game puzzles | 84.0% | Not measured | Only GPT-6 Astra measured |
| EBR-bench | 76.2% | Not measured | Only GPT-6 Astra measured |
| LMArena Text: hard prompts | 1463 | 1362 | GPT-6 Astra |
| LMArena Text: expert | 1489 | 1358 | GPT-6 Astra |
| LMArena Text: hard prompts in English | 1464 | 1374 | GPT-6 Astra |
| LMArena Vision: diagrams | 1297 | Not measured | Only GPT-6 Astra measured |
| LMArena Vision: homework | 1337 | Not measured | Only GPT-6 Astra measured |
| Neither model has a result on the other 7 boards here | |||
MathDirectional onlyPublic boards, shown as published, kept out of the index6 boards, none shared
| Benchmark | GPT-6 Astra | Mercury 2 | Leader |
|---|---|---|---|
| OTIS Mock AIME | 100.0% | Not measured | Only GPT-6 Astra measured |
| FrontierMath, tiers 1 to 3 | 93.7% | Not measured | Only GPT-6 Astra measured |
| FrontierMath, tier 4 | 97.6% | Not measured | Only GPT-6 Astra measured |
| ProofBench | 99.0% | Not measured | Only GPT-6 Astra measured |
| LMArena Text: math | 1465 | Not measured | Only GPT-6 Astra measured |
| LMArena Text: mathematical work | 1484 | Not measured | Only GPT-6 Astra measured |
| Neither model has a result on the other 7 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index30
| Benchmark | GPT-6 Astra | Mercury 2 | Leader |
|---|---|---|---|
| MedCode (Vals AI) | 48.5% | Not measured | Only GPT-6 Astra measured |
| SimpleQA Verified | 75.6% | Not measured | Only GPT-6 Astra measured |
| LMArena Text: science | 1451 | 1343 | GPT-6 Astra |
| LMArena Text: medicine and healthcare | 1425 | 1363 | GPT-6 Astra |
| LMArena Text: legal and government | 1462 | Not measured | Only GPT-6 Astra measured |
| LMArena Text: business and finance | 1439 | 1349 | GPT-6 Astra |
| FACTS Benchmark Suite | 75.7% | Not measured | Only GPT-6 Astra measured |
| Neither model has a result on the other 11 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index80
| Benchmark | GPT-6 Astra | Mercury 2 | Leader |
|---|---|---|---|
| Design Arena: websites | 1336 | 1035 | GPT-6 Astra |
| Design Arena: UI components | 1394 | 996 | GPT-6 Astra |
| Design Arena: game dev | 1479 | 983 | GPT-6 Astra |
| Design Arena: data viz | 1334 | 1010 | GPT-6 Astra |
| Design Arena: 3D | 1500 | 982 | GPT-6 Astra |
| Design Arena: all code categories | 1378 | 1020 | GPT-6 Astra |
| Design Arena: SVG | 1430 | 996 | GPT-6 Astra |
| Design Arena: ASCII art | 1353 | 988 | GPT-6 Astra |
| LiveBench design | 82.0% | Not measured | Only GPT-6 Astra measured |
GeneralLike-for-likePublic boards, shown as published, kept out of the index120
| Benchmark | GPT-6 Astra | Mercury 2 | Leader |
|---|---|---|---|
| Vals Index | 65.0% | Not measured | Only GPT-6 Astra measured |
| LiveBench data analysis | 83.0% | Not measured | Only GPT-6 Astra measured |
| SAGE (Vals AI) | 46.4% | Not measured | Only GPT-6 Astra measured |
| MedScribe (Vals AI) | 87.9% | Not measured | Only GPT-6 Astra measured |
| IFBench | Not measured | 69.8% | Only Mercury 2 measured |
| Long context reasoning (AA-LCR) | 80.7% | 43.7% | GPT-6 Astra |
| DTBench | 97.3% | Not measured | Only GPT-6 Astra measured |
| LMCA | 64.4% | Not measured | Only GPT-6 Astra measured |
| Furniture assembly | 80.0% | Not measured | Only GPT-6 Astra measured |
| LMArena Text | 1441 | 1354 | GPT-6 Astra |
| LMArena Text: instruction following | 1455 | 1328 | GPT-6 Astra |
| LMArena Text: creative writing | 1420 | 1286 | GPT-6 Astra |
| LMArena Vision | 1280 | Not measured | Only GPT-6 Astra measured |
| LMArena Text: English | 1447 | 1378 | GPT-6 Astra |
| LMArena Text: non-English | 1432 | 1330 | GPT-6 Astra |
| LMArena Text: Chinese | 1489 | 1414 | GPT-6 Astra |
| LMArena Text: German | 1459 | Not measured | Only GPT-6 Astra measured |
| LMArena Text: Japanese | 1405 | Not measured | Only GPT-6 Astra measured |
| LMArena Text: Korean | 1428 | Not measured | Only GPT-6 Astra measured |
| LMArena Text: French | 1432 | Not measured | Only GPT-6 Astra measured |
| LMArena Text: Spanish | 1422 | Not measured | Only GPT-6 Astra measured |
| LMArena Text: Russian | 1438 | 1304 | GPT-6 Astra |
| LMArena Text: Polish | 1422 | Not measured | Only GPT-6 Astra measured |
| LMArena Text: multi-turn | 1447 | 1357 | GPT-6 Astra |
| LMArena Text: longer queries | 1460 | 1329 | GPT-6 Astra |
| LMArena Text: writing and language | 1437 | 1300 | GPT-6 Astra |
| LMArena Text: entertainment and media | 1427 | 1314 | GPT-6 Astra |
| LMArena Vision: English | 1280 | Not measured | Only GPT-6 Astra measured |
| LMArena Vision: Chinese | 1361 | Not measured | Only GPT-6 Astra measured |
| LMArena Vision: reading text | 1292 | Not measured | Only GPT-6 Astra measured |
| LMArena Vision: creative writing | 1286 | Not measured | Only GPT-6 Astra measured |
| Neither model has a result on the other 15 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | GPT-6 Astra | Mercury 2 | Leader |
|---|---|---|---|
| Neither model has a result on 5 boards here | |||
What each workload costs
Three fixed token mixes at each model's listed price, so per-token rates become a bill.
Chat turn
1K input + 500 output tokens
GPT-6 Astra$0.035Fits in one request
Mercury 2$0.0006Fits in one request
Mercury 2 costs less
Repository review
50K input + 3K output tokens
GPT-6 Astra$0.650Fits in one request
Mercury 2$0.015Fits in one request
Mercury 2 costs less
Agent loop
200K input + 10K output tokens
GPT-6 Astra$2.50Fits in one request
Mercury 2$0.058Exceeds the context window
Mercury 2 costs less
Listed OpenRouter rates, without cache or batch discounts. A workload that does not fit a model's context window would need splitting.
Specification differences
The leading value in a row is marked; a row with a missing value names no leader. Our two rows are marked in red.
| Specification | OpenAI GPT-6 Astra | Inception Mercury 2 |
|---|---|---|
| Maker | OpenAI | Inception |
| Weights | No public weights listed | No public weights listed |
| Released | September 4, 2026 | March 4, 2026 |
| Context window | 1.05M | 128K |
| Input $/Mtok | $10.00 | $0.25 |
| Output $/Mtok | $50.00 | $0.75 |
| Coding index | 85.1 | Not benchmarked |
| Independent measurements behind it | 5 | 1 |
| Cost per solved task | Not computable | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is GPT-6 Astra better than Mercury 2 for coding?
Only GPT-6 Astra has a coding score, 85.1 on the Vibe Coding Index; Mercury 2 has none, so the two cannot be ranked on coding. Pick Mercury 2 for output tokens 66.7x cheaper ($0.75 vs $50.00 per million).
Which is cheaper, GPT-6 Astra or Mercury 2?
GPT-6 Astra costs $10.00 per million input tokens and $50.00 per million output tokens; Mercury 2 costs $0.25 and $0.75. Cost per solved task is known for neither of them.
Which has the bigger context window, GPT-6 Astra or Mercury 2?
GPT-6 Astra, with 1.05M tokens against 128K.
How many benchmarks is the GPT-6 Astra vs Mercury 2 comparison based on?
39 benchmarks have a result for both models as of October 22, 2026. GPT-6 Astra's coding index rests on 5 independent benchmarks and Mercury 2's on 1. Where only one model has a result, the page says so instead of naming a winner.