Gemma 4 26B A4B vs GPT-5.6 Luna

GPT-5.6 Luna leads Gemma 4 26B A4B on the Artificial Analysis Intelligence Index, 37.3 to 16.7, and Gemma 4 26B A4B costs 2.0x less per output token ($0.60 vs $1.20 per million). Updated October 22, 2026; 50 benchmarks have a result for both.

Replace Gemma 4 26B A4B Replace GPT-5.6 Luna

Gemma 4 26B A4BGoogle

Coding: No data
Overall: 54.7
Output $/M: $0.60

GPT-5.6 LunaOpenAI

Coding: 58.0
Overall: 61.6
Output $/M: $1.20

vs boards won of 50 shared

Gemma 4 26B A4B or GPT-5.6 Luna: which to pick

Only GPT-5.6 Luna has a coding score, 58.0 on the Vibe Coding Index; Gemma 4 26B A4B has none, so the two cannot be ranked on coding.

Pick Gemma 4 26B A4B for output tokens 2.0x cheaper ($0.60 vs $1.20 per million) and work measured by LMArena Vision: homework or LMArena Text: math, where it leads.

Model AGemma 4 26B A4BGoogleNot benchmarked1 independent benchmarkNo cost per solved task Model BGPT-5.6 LunaOpenAI58.0/1006 independent benchmarks$0.04 per solved task

50569

Shared results: 50
Gemma 4 26B A4B only: 5
GPT-5.6 Luna only: 69
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-5.6 Luna has a coding score, so no call is made.
One side not measured
Intelligence
AA Intelligence Index
GPT-5.6 Luna
GPT-5.6 Luna leads, 37.3 against 16.7.
Same board, both measured
Agentic work
AA Agentic Index
GPT-5.6 Luna
GPT-5.6 Luna leads, 42.1 against 2.9.
Same board, both measured
Reasoning
GPQA Diamond
No call
Only GPT-5.6 Luna has a GPQA Diamond result, 91.7%.
Directional only
Knowledge
MMLU Pro
No call
Only GPT-5.6 Luna has a MMLU Pro result, 86.0%.
Directional only
Web design
Design Arena: websites
No call
Only GPT-5.6 Luna has a Design Arena: websites result, 1255.
Directional only
Long documents
Listed context window
GPT-5.6 Luna
GPT-5.6 Luna takes 1.05M tokens against 262K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Gemma 4 26B A4B
Gemma 4 26B A4B $0.0004, GPT-5.6 Luna $0.0008 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only GPT-5.6 Luna has the number, $0.04.
Directional only

At a glance

Coding index: Gemma 4 26B A4B not benchmarked, GPT-5.6 Luna 58.0 from 6 benchmarks.
Widest category: Agentic work, 39.2 points apart on average over 1 shared benchmark.
Widest single gap: AA Agentic Index: Gemma 4 26B A4B 2.9 against GPT-5.6 Luna 42.1, 39.2 points apart on a 0 to 100 scale.
Output price: Gemma 4 26B A4B $0.60 against GPT-5.6 Luna $1.20 per million output tokens, 2.0x apart.
Context window: Gemma 4 26B A4B takes 262K tokens, GPT-5.6 Luna 1.05M.

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.

Boards won, where both have a result
Category	Gemma 4 26B A4B	GPT-5.6 Luna
Coding	0	9
Intelligence	0	2
Agentic work	0	1
Reasoning	1	7
Math	2	1
Knowledge	4	1
General	13	9
All shared boards	20	30

CodingLike-for-likeSix of these boards feed the Vibe Coding Index09

Coding benchmarks for Gemma 4 26B A4B and GPT-5.6 Luna
Benchmark	Gemma 4 26B A4B	GPT-5.6 Luna	Leader
LiveBench coding	Not measured	73.6%	Only GPT-5.6 Luna measured
LMArena WebDev	1360	1518	GPT-5.6 Luna
AA Coding Index	39.3	71.4	GPT-5.6 Luna
SWE-bench Verified (Vals AI)	Not measured	93.0%	Only GPT-5.6 Luna measured
Terminal-Bench 4 (Vals AI)	Not measured	11.6%	Only GPT-5.6 Luna measured
Vibe Code Bench (Vals AI)	Not measured	77.1%	Only GPT-5.6 Luna measured
Code migration (Vals AI)	Not measured	44.5%	Only GPT-5.6 Luna measured
ProgramBench (Vals AI)	Not measured	0.0%	Only GPT-5.6 Luna measured
IOI (Vals AI)	Not measured	61.8%	Only GPT-5.6 Luna measured
Terminal-Bench 2.1 (Vals AI)	Not measured	79.0%	Only GPT-5.6 Luna measured
Vibe Code Bench 1-100 (Vals AI)	Not measured	22.6%	Only GPT-5.6 Luna measured
SkillsBench (Vals AI)	Not measured	60.5%	Only GPT-5.6 Luna measured
CyberBench (Vals AI)	Not measured	73.6%	Only GPT-5.6 Luna measured
SciCode	40.0%	53.6%	GPT-5.6 Luna
Terminal-Bench Hard (Artificial Analysis run)	25.0%	Not measured	Only Gemma 4 26B A4B measured
FrontierCode	Not measured	39.8%	Only GPT-5.6 Luna measured
WeirdML	35.2%	60.9%	GPT-5.6 Luna
ALE-Bench	927.2	1667.4	GPT-5.6 Luna
LMArena Text: coding	1446	1466	GPT-5.6 Luna
LMArena Text: software and IT	1454	1463	GPT-5.6 Luna
LMArena WebDev: React	1351	1508	GPT-5.6 Luna
LMArena WebDev: HTML	1362	1520	GPT-5.6 Luna
LMArena WebDev: from an image	Not measured	1517	Only GPT-5.6 Luna measured
SciCode	Not measured	6.2%	Only GPT-5.6 Luna measured
Neither model has a result on the other 15 boards here

IntelligenceLike-for-likePublic boards, shown as published, kept out of the index02

Intelligence benchmarks for Gemma 4 26B A4B and GPT-5.6 Luna
Benchmark	Gemma 4 26B A4B	GPT-5.6 Luna	Leader
AA Intelligence Index	16.7	37.3	GPT-5.6 Luna
Epoch Capabilities Index	141.9	156.5	GPT-5.6 Luna

Agentic workLike-for-likePublic boards, shown as published, kept out of the index01

Agentic work benchmarks for Gemma 4 26B A4B and GPT-5.6 Luna
Benchmark	Gemma 4 26B A4B	GPT-5.6 Luna	Leader
AA Agentic Index	2.9	42.1	GPT-5.6 Luna
LiveBench research	Not measured	51.0%	Only GPT-5.6 Luna measured
LiveBench browser	Not measured	68.0%	Only GPT-5.6 Luna measured
LiveBench long agentic	Not measured	30.4%	Only GPT-5.6 Luna measured
SREBench (Vals AI)	Not measured	1.5%	Only GPT-5.6 Luna measured
Finance Agent (Vals AI)	Not measured	55.0%	Only GPT-5.6 Luna measured
Tax Agent Bench (Vals AI)	Not measured	24.8%	Only GPT-5.6 Luna measured
Legal Research Bench (Vals AI)	Not measured	36.5%	Only GPT-5.6 Luna measured
Excel Modeling Benchmark (Vals AI)	Not measured	67.1%	Only GPT-5.6 Luna measured
BioMysteryBench (Vals AI)	Not measured	61.5%	Only GPT-5.6 Luna measured
Terminal-Bench-Science (Vals AI)	Not measured	0.0%	Only GPT-5.6 Luna measured
Vals Science Index	Not measured	25.3%	Only GPT-5.6 Luna measured
τ²-Bench Telecom	43.6%	Not measured	Only Gemma 4 26B A4B measured
APEX-Agents	Not measured	43.0%	Only GPT-5.6 Luna measured
BALROG	Not measured	45.6%	Only GPT-5.6 Luna measured
Vending-Bench 2	Not measured	$4,095	Only GPT-5.6 Luna measured
Neither model has a result on the other 25 boards here

ReasoningLike-for-likePublic boards, shown as published, kept out of the index17

Reasoning benchmarks for Gemma 4 26B A4B and GPT-5.6 Luna
Benchmark	Gemma 4 26B A4B	GPT-5.6 Luna	Leader
GPQA Diamond	Not measured	91.7%	Only GPT-5.6 Luna measured
LiveBench reasoning	Not measured	85.6%	Only GPT-5.6 Luna measured
MysteryMechanism (Vals AI)	Not measured	14.4%	Only GPT-5.6 Luna measured
MMMU Pro (Vals AI)	Not measured	85.0%	Only GPT-5.6 Luna measured
GPQA Diamond (Artificial Analysis run)	79.2%	91.1%	GPT-5.6 Luna
Humanity's Last Exam (Artificial Analysis run)	19.3%	39.5%	GPT-5.6 Luna
GPQA Diamond (Epoch AI run)	73.2%	91.6%	GPT-5.6 Luna
ARC-AGI	Not measured	88.0%	Only GPT-5.6 Luna measured
ARC-AGI-2	Not measured	59.5%	Only GPT-5.6 Luna measured
SimpleBench	Not measured	46.8%	Only GPT-5.6 Luna measured
Chess puzzles	Not measured	43.0%	Only GPT-5.6 Luna measured
Mystery game puzzles	Not measured	21.0%	Only GPT-5.6 Luna measured
LMArena Text: hard prompts	1438	1451	GPT-5.6 Luna
LMArena Text: expert	1447	1478	GPT-5.6 Luna
LMArena Text: hard prompts in English	1448	1460	GPT-5.6 Luna
LMArena Vision: diagrams	1264	1273	GPT-5.6 Luna
LMArena Vision: homework	1293	1282	Gemma 4 26B A4B
Kagi LLM Benchmark	Not measured	49.1%	Only GPT-5.6 Luna measured
Neither model has a result on the other 4 boards here

MathLike-for-likePublic boards, shown as published, kept out of the index21

Math benchmarks for Gemma 4 26B A4B and GPT-5.6 Luna
Benchmark	Gemma 4 26B A4B	GPT-5.6 Luna	Leader
OTIS Mock AIME	82.2%	98.3%	GPT-5.6 Luna
FrontierMath, tiers 1 to 3	Not measured	82.1%	Only GPT-5.6 Luna measured
FrontierMath, tier 4	Not measured	61.0%	Only GPT-5.6 Luna measured
ProofBench	Not measured	60.0%	Only GPT-5.6 Luna measured
LMArena Text: math	1470	1459	Gemma 4 26B A4B
LMArena Text: mathematical work	1475	1470	Gemma 4 26B A4B
Neither model has a result on the other 7 boards here

KnowledgeLike-for-likePublic boards, shown as published, kept out of the index41

Knowledge benchmarks for Gemma 4 26B A4B and GPT-5.6 Luna
Benchmark	Gemma 4 26B A4B	GPT-5.6 Luna	Leader
MMLU Pro	Not measured	86.0%	Only GPT-5.6 Luna measured
LegalBench (Vals AI)	Not measured	84.0%	Only GPT-5.6 Luna measured
CorpFin (Vals AI)	Not measured	64.2%	Only GPT-5.6 Luna measured
TaxEval (Vals AI)	Not measured	76.2%	Only GPT-5.6 Luna measured
MortgageTax (Vals AI)	Not measured	67.3%	Only GPT-5.6 Luna measured
MedCode (Vals AI)	Not measured	42.4%	Only GPT-5.6 Luna measured
SimpleQA Verified	Not measured	41.0%	Only GPT-5.6 Luna measured
LMArena Text: science	1446	1433	Gemma 4 26B A4B
LMArena Text: medicine and healthcare	1428	1399	Gemma 4 26B A4B
LMArena Text: legal and government	1457	1446	Gemma 4 26B A4B
LMArena Text: business and finance	1429	1439	GPT-5.6 Luna
FACTS Benchmark Suite	42.7%	35.0%	Gemma 4 26B A4B
Neither model has a result on the other 6 boards here

Web designDirectional onlyPublic boards, shown as published, kept out of the index9 boards, none shared

Web design benchmarks for Gemma 4 26B A4B and GPT-5.6 Luna
Benchmark	Gemma 4 26B A4B	GPT-5.6 Luna	Leader
Design Arena: websites	Not measured	1255	Only GPT-5.6 Luna measured
Design Arena: UI components	Not measured	1248	Only GPT-5.6 Luna measured
Design Arena: game dev	Not measured	1194	Only GPT-5.6 Luna measured
Design Arena: data viz	Not measured	1211	Only GPT-5.6 Luna measured
Design Arena: 3D	Not measured	1121	Only GPT-5.6 Luna measured
Design Arena: all code categories	Not measured	1231	Only GPT-5.6 Luna measured
Design Arena: SVG	Not measured	1194	Only GPT-5.6 Luna measured
Design Arena: ASCII art	Not measured	1142	Only GPT-5.6 Luna measured
LiveBench design	Not measured	76.0%	Only GPT-5.6 Luna measured

GeneralLike-for-likePublic boards, shown as published, kept out of the index139

General benchmarks for Gemma 4 26B A4B and GPT-5.6 Luna
Benchmark	Gemma 4 26B A4B	GPT-5.6 Luna	Leader
LiveBench data analysis	Not measured	78.0%	Only GPT-5.6 Luna measured
Public Benefits Bench (Vals AI)	Not measured	61.2%	Only GPT-5.6 Luna measured
SAGE (Vals AI)	Not measured	44.2%	Only GPT-5.6 Luna measured
MedScribe (Vals AI)	Not measured	84.4%	Only GPT-5.6 Luna measured
Vals Multimodal Index	Not measured	69.1%	Only GPT-5.6 Luna measured
IFBench	72.4%	Not measured	Only Gemma 4 26B A4B measured
Long context reasoning (AA-LCR)	65.7%	83.7%	GPT-5.6 Luna
DTBench	74.9%	89.1%	GPT-5.6 Luna
LMCA	29.7%	48.5%	GPT-5.6 Luna
Surface Evolver Bench	Not measured	61.9%	Only GPT-5.6 Luna measured
Furniture assembly	Not measured	42.5%	Only GPT-5.6 Luna measured
LMArena Text	1434	1431	Gemma 4 26B A4B
LMArena Text: instruction following	1420	1437	GPT-5.6 Luna
LMArena Text: creative writing	1400	1396	Gemma 4 26B A4B
LMArena Vision	1260	1257	Gemma 4 26B A4B
LMArena Text: English	1444	1441	Gemma 4 26B A4B
LMArena Text: non-English	1421	1417	Gemma 4 26B A4B
LMArena Text: Chinese	1495	1470	Gemma 4 26B A4B
LMArena Text: German	Not measured	1455	Only GPT-5.6 Luna measured
LMArena Text: Japanese	Not measured	1415	Only GPT-5.6 Luna measured
LMArena Text: Korean	Not measured	1415	Only GPT-5.6 Luna measured
LMArena Text: French	1460	1458	Gemma 4 26B A4B
LMArena Text: Spanish	1415	1446	GPT-5.6 Luna
LMArena Text: Russian	1434	1427	Gemma 4 26B A4B
LMArena Text: Polish	Not measured	1405	Only GPT-5.6 Luna measured
LMArena Text: multi-turn	1441	1434	Gemma 4 26B A4B
LMArena Text: longer queries	1427	1436	GPT-5.6 Luna
LMArena Text: writing and language	1405	1419	GPT-5.6 Luna
LMArena Text: entertainment and media	1403	1402	Gemma 4 26B A4B
LMArena Vision: English	1256	1263	GPT-5.6 Luna
LMArena Vision: Chinese	1312	1294	Gemma 4 26B A4B
LMArena Vision: reading text	1268	1264	Gemma 4 26B A4B
LMArena Vision: humor	1272	1190	Gemma 4 26B A4B
LMArena Vision: captioning	1297	Not measured	Only Gemma 4 26B A4B measured
LMArena Vision: recognizing things	1191	Not measured	Only Gemma 4 26B A4B measured
LMArena Vision: creative writing	1256	1257	GPT-5.6 Luna
LMArena Document	Not measured	1457	Only GPT-5.6 Luna measured
Neither model has a result on the other 9 boards here

Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared

Image generation benchmarks for Gemma 4 26B A4B and GPT-5.6 Luna
Benchmark	Gemma 4 26B A4B	GPT-5.6 Luna	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

Gemma 4 26B A4B$0.0004Fits in one request

GPT-5.6 Luna$0.0008Fits in one request

Gemma 4 26B A4B costs less

Repository review

50K input + 3K output tokens

Gemma 4 26B A4B$0.0093Fits in one request

GPT-5.6 Luna$0.014Fits in one request

Gemma 4 26B A4B costs less

Agent loop

200K input + 10K output tokens

Gemma 4 26B A4B$0.036Fits in one request

GPT-5.6 Luna$0.052Fits in one request

Gemma 4 26B A4B 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.

Specifications of Gemma 4 26B A4B and GPT-5.6 Luna
Specification	Google Gemma 4 26B A4B	OpenAI GPT-5.6 Luna
Maker	Google	OpenAI
Weights	Open weights	No public weights listed
Released	April 3, 2026	July 9, 2026
Context window	262K	1.05M
Input $/Mtok	$0.15	$0.20
Output $/Mtok	$0.60	$1.20
Coding index	Not benchmarked	58.0
Independent measurements behind it	1	6
Cost per solved task	Not computable	$0.04
Source	OpenRouter listing	OpenRouter listing

Questions

Is Gemma 4 26B A4B better than GPT-5.6 Luna for coding?

Only GPT-5.6 Luna has a coding score, 58.0 on the Vibe Coding Index; Gemma 4 26B A4B has none, so the two cannot be ranked on coding. Pick Gemma 4 26B A4B for output tokens 2.0x cheaper ($0.60 vs $1.20 per million) and work measured by LMArena Vision: homework or LMArena Text: math, where it leads.

Which is cheaper, Gemma 4 26B A4B or GPT-5.6 Luna?

Gemma 4 26B A4B costs $0.15 per million input tokens and $0.60 per million output tokens; GPT-5.6 Luna costs $0.20 and $1.20. Cost per solved task is known for GPT-5.6 Luna only.

Which has the bigger context window, Gemma 4 26B A4B or GPT-5.6 Luna?

GPT-5.6 Luna, with 1.05M tokens against 262K.

How many benchmarks is the Gemma 4 26B A4B vs GPT-5.6 Luna comparison based on?

50 benchmarks have a result for both models as of October 22, 2026. Gemma 4 26B A4B's coding index rests on 1 independent benchmark and GPT-5.6 Luna's on 6. Where only one model has a result, the page says so instead of naming a winner.

Gemma 4 26B A4B or GPT-5.6 Luna: which to pick

Which one for your work

Coding

Intelligence

Agentic work

Reasoning

Knowledge

Web design

Long documents

Everyday cost

Cost per solved task

At a glance

Benchmark by benchmark

What each workload costs

Chat turn

Repository review

Agent loop

Specification differences

Questions

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