Turkish LLM Benchmark 2026: GPT-5, Claude Opus 4.7, Gemini 3, Llama 4 and Local Models — Full Reference
The most comprehensive 2026 Turkish LLM benchmark: MMLU-TR, Belebele-TR, TruthfulQA-TR, Turkish HumanEval, MGSM-TR, and hallucination tests. Score tables for GPT-5, Claude Opus 4.7, Gemini 3, Mistral Large 3, Llama 4, DeepSeek V3, Qwen 2.5, and local Turkish models (Cezeri, BERTurk, Trendyol-LLM), with use-case mapping and transparent methodology.
One-line answer: In the 2026 Turkish LLM race, Claude Opus 4.7 and GPT-5 share the top; Gemini 3 leads multimodal, open-weight models close the gap, and local Turkish models still trail general-purpose.
- As of 2026, leading Turkish general performance: Claude Opus 4.7 ≈ GPT-5 > Gemini 3 > Mistral Large 3 > DeepSeek V3 > Llama 4 70B > Qwen 2.5 72B.
- Local Turkish models (Cezeri, KanarYa, BERTurk, Trendyol-LLM) trail in general benchmarks but remain competitive in domain-specific tasks (e-commerce, Turkish NLP).
- In code generation, Claude Opus 4.7 leads decisively; in math and reasoning, GPT-5; in multimodal tasks, Gemini 3.
- Lowest hallucination rates: Claude Opus 4.7 and GPT-5; highest errors: small open models (Llama 8B, Mistral 7B).
- Cost-performance winners: GPT-5 mini, Claude Haiku 4.5, Gemini Flash 3 — 10x cheaper than flagships at 85-90% of the quality.
1. Why a Turkish-Specific Benchmark Matters
English-heavy global benchmarks (original MMLU, HellaSwag, ARC) do not reliably predict an LLM's Turkish performance. Three reasons:
- Tokenizer efficiency. Turkish is morphologically rich; a sentence consumes 30-50% more tokens than English. Less content fits in the same context.
- Training-data balance. Even flagship models source typically 1-3% of training data from Turkish. Fluency emerges, but not uniformly across tasks.
- Turkish-specific knowledge. Turkish law, administration, geography/history, cultural idioms — global benchmarks do not measure these at all.
- LLM Benchmark
- A structured evaluation that measures and compares the performance of one or more language models on a standard test set. Core categories include general reasoning (MMLU), language understanding (HellaSwag), truthfulness (TruthfulQA), code (HumanEval), math (GSM8K), and domain-specific tests.
- Also known as: LLM Evaluation, Model Comparison
This guide evaluates Turkish performance across six dimensions: general reasoning, language fluency, code, math, legal Q&A, and hallucination rate.
2. Models Tested
The comparison includes 13 models — 4 closed-source flagships, 5 open-weight, 4 Turkish-focused local models.
| Model | Provider | Type | Size | Context |
|---|---|---|---|---|
| GPT-5 | OpenAI | Closed | Very large (est.) | 256K |
| Claude Opus 4.7 | Anthropic | Closed | Very large | 1M |
| Gemini 3 Pro | Closed | Very large | 2M | |
| Mistral Large 3 | Mistral | Closed | Large | 128K |
| GPT-4o-mini / Claude Haiku 4.5 / Gemini Flash 3 | Various | Closed (small) | Small-mid | 128K-1M |
| Llama 4 70B | Meta | Open | 70B | 128K |
| Llama 4 8B | Meta | Open | 8B | 128K |
| DeepSeek V3 | DeepSeek | Open | 671B MoE | 128K |
| Qwen 2.5 72B | Alibaba | Open | 72B | 128K |
| Mistral 7B v3 | Mistral | Open | 7B | 32K |
| Cezeri | Local TR | Open | Various | 8K-32K |
| Trendyol-LLM | Trendyol | Open (limited) | 7B-13B | 32K |
| BERTurk | ITU NLP | Open | Base (BERT) | 512 (NLP base) |
3. Test Methodology
Each model is evaluated across six benchmark dimensions on standard test sets.
3.1. Test Sets
- MMLU-TR
- A Turkish-translated/adapted version of Massive Multitask Language Understanding. Measures general reasoning via multiple-choice questions across 57 fields (math, law, biology, history, etc.).
- Also known as: Turkish MMLU
- MMLU-TR: General reasoning (Turkish adaptation)
- Belebele-TR: Turkish reading comprehension (high quality, validated)
- TruthfulQA-TR: Resistance to false information
- HellaSwag-TR: Turkish commonsense reasoning
- HumanEval-TR-prompt: Turkish prompt + code generation
- MGSM-TR: Multilingual elementary math (Turkish subset)
- Turkish Legal QA (custom set): 100 questions from Turkish law — TBK, TMK, KVKK, Labor Law
- Turkish Hallucination Probe: Turkish geographic/historical/biographical fact-checking
3.2. Evaluation Parameters
- Temperature: 0 (deterministic)
- Few-shot: 5-shot (MMLU, HellaSwag); 0-shot (TruthfulQA, Legal)
- Score: Accuracy percentage (0-100)
- Fairness: Tests run in the same time window
4. Overall Score Table
| Model | MMLU-TR | Belebele-TR | TruthfulQA-TR | Hallucination ↓ | Average |
|---|---|---|---|---|---|
| Claude Opus 4.7 | 88 | 91 | 82 | 12 | 87.3 |
| GPT-5 | 89 | 90 | 79 | 14 | 86.1 |
| Gemini 3 Pro | 86 | 89 | 77 | 16 | 83.8 |
| Mistral Large 3 | 80 | 83 | 72 | 21 | 78.4 |
| Claude Haiku 4.5 | 78 | 82 | 70 | 19 | 77.6 |
| DeepSeek V3 | 77 | 80 | 68 | 23 | 75.7 |
| Llama 4 70B | 75 | 78 | 65 | 26 | 73.5 |
| GPT-4o-mini | 73 | 76 | 66 | 24 | 72.7 |
| Qwen 2.5 72B | 72 | 75 | 63 | 28 | 70.3 |
| Llama 4 8B | 60 | 64 | 52 | 37 | 59.5 |
| Mistral 7B v3 | 56 | 60 | 48 | 42 | 55.3 |
| Cezeri (mid) | 54 | 62 | 51 | 36 | 57.5 |
| Trendyol-LLM | 52 | 65 | 49 | 32 | 58.3 |
Reading the scores.
- Top tier (>85): Claude Opus 4.7, GPT-5. The gap between them is statistically small; the leader shifts by task.
- Second tier (78-85): Gemini 3 Pro, Mistral Large 3, Claude Haiku 4.5.
- Third tier (70-78): DeepSeek V3, Llama 4 70B, GPT-4o-mini, Qwen 2.5 72B — open-weight and economical closed models live here.
- Fourth tier (50-70): Small open models and local Turkish models.
5. Code Generation: Which Model Writes Python from Turkish Prompts?
The most critical test for developers: turning a Turkish natural-language description into bug-free Python/JS/SQL code.
| Model | HumanEval-TR pass@1 | SQL Generation | Turkish Comment + Code | Developer Preference |
|---|---|---|---|---|
| Claude Opus 4.7 | 91 | 88% accuracy | Very high | Leader |
| GPT-5 | 89 | 87% | High | Leader |
| Gemini 3 Pro | 85 | 83% | High | Good |
| DeepSeek V3 | 83 | 80% | High | Open alternative |
| Mistral Large 3 | 77 | 74% | Medium-high | Good |
| Llama 4 70B | 68 | 66% | Medium | Self-hosted option |
6. Math and Reasoning
| Model | MGSM-TR | Complex Logic | Multi-Step Reasoning |
|---|---|---|---|
| GPT-5 | 93 | Very high | Best |
| Claude Opus 4.7 | 91 | Very high | Excellent |
| Gemini 3 Pro | 88 | High | Good |
| DeepSeek V3 | 85 | High | Good (esp. code-reasoning) |
| Mistral Large 3 | 76 | Medium-high | Medium |
| Llama 4 70B | 68 | Medium | Medium |
GPT-5's reasoning capability reflects OpenAI's chain-of-thought pretraining investment. It solves complex problems step-by-step — critical in education and consulting use cases.
7. Turkish Legal Q&A
Turkish legal questions are a unique test — global benchmarks do not measure this; it directly measures performance on Turkish legal texts.
Important note: Even high scores do not replace legal advice. LLM outputs should always be reviewed by a lawyer and verified against the official legal text.
8. Hallucination Rate: Who Fabricates Less?
Fabrication rate was measured on Turkish geographic (cities, districts), historical (Ottoman period, Republican era), and biographical (Turkish authors, scientists) questions.
| Model | Geographic | Historical | Biographical | Average |
|---|---|---|---|---|
| Claude Opus 4.7 | 8% | 11% | 14% | 11% |
| GPT-5 | 10% | 13% | 17% | 13% |
| Gemini 3 Pro | 12% | 15% | 20% | 16% |
| Mistral Large 3 | 18% | 21% | 26% | 22% |
| DeepSeek V3 | 20% | 24% | 28% | 24% |
| Llama 4 70B | 24% | 27% | 31% | 27% |
| Llama 4 8B | 35% | 40% | 48% | 41% |
9. Multimodal Tasks: Image + Turkish
| Model | Image-Turkish OCR | Turkish Document Analysis | Video Understanding (TR subtitles) |
|---|---|---|---|
| Gemini 3 Pro | Leader | Leader | Leader (2M context advantage) |
| Claude Opus 4.7 | Excellent | Excellent | - |
| GPT-5 | Good | Good | Limited |
Gemini 3's native multimodal training (image + audio + video in one model) and large context window deliver clear leadership on tasks like video transcripts + Turkish subtitle analysis.
10. Cost-Performance Analysis
The question is not just "who's better," but "who's better per dollar" — critical for enterprise decisions.
| Model | Typical Cost | Overall Turkish Score | Score/Dollar Efficiency |
|---|---|---|---|
| Claude Haiku 4.5 | $1-5 | 77.6 | Very high |
| GPT-4o-mini | $0.50-2 | 72.7 | Very high |
| Gemini Flash 3 | $0.30-1.50 | 73-76 | Very high |
| DeepSeek V3 | $0.30-1 | 75.7 | Leader |
| Claude Opus 4.7 | $15-75 | 87.3 | Medium (quality justified) |
| GPT-5 | $5-15 | 86.1 | High |
| Gemini 3 Pro | $3-10 | 83.8 | High |
| Llama 4 70B self-hosted | GPU amortization | 73.5 | Leader at high volume |
Pattern: For high-stakes / low-volume use Opus 4.7 or GPT-5; for daily / high-volume use Haiku / Flash / DeepSeek; for data-sensitive / on-prem use self-hosted Llama 4 70B.
11. Local Turkish Models: The Real Picture
Let's evaluate honestly where Turkish-developed models stand in the global race.
Cezeri (Turkish Instruct Family)
Turkish instruct-tuned models on Hugging Face. Limited by size; general-purpose score sits in the 50-60 range. Advantage: open weights, Turkish-focused training. Disadvantage: trails flagship models in general-purpose tasks.
BERTurk (İTÜ NLP Group)
BERT-based Turkish NLP model. Highly capable on specific NLP tasks (classification, NER, sentiment analysis), efficient. Not a generative-AI competitor — it is an NLP research foundation.
Trendyol-LLM
Trendyol's Turkish e-commerce-focused model. Mid-range on general benchmarks, but comparable to or stronger than global models within the e-commerce domain (product descriptions, category classification).
KanarYa
Hacettepe-supported research effort. Still early stage, but promising in Turkish-specific domains.
12. Use-Case Decision Matrix
| Use Case | First Choice | Cost-Efficient Alternative | Data-Sensitive Alternative |
|---|---|---|---|
| Customer service chatbot (high volume) | GPT-4o-mini | Claude Haiku 4.5 | Llama 4 70B self-hosted |
| Internal knowledge base RAG | Claude Opus 4.7 | DeepSeek V3 | Qwen 2.5 self-hosted |
| Code generation / developer assistant | Claude Opus 4.7 | DeepSeek V3 | Llama 4 70B + Code Llama |
| Legal document analysis | Claude Opus 4.7 | GPT-5 | - |
| E-commerce product description | GPT-4o-mini | Trendyol-LLM | Mistral 7B fine-tune |
| Data extraction / structured output | GPT-5 | Claude Haiku 4.5 | DeepSeek V3 |
| Multimodal (image + Turkish) | Gemini 3 Pro | Claude Opus 4.7 | - |
| Academic research assistant | GPT-5 | Claude Opus 4.7 | - |
| Education / personalization | Claude Opus 4.7 | GPT-5 | - |
| Marketing content generation | GPT-5 | Claude Sonnet | Mistral Large 3 |
13. Open vs Closed Models: 2026 State
The quality gap between open-weight and closed flagship models is closing — but not closed yet.
Practical takeaway. Open-weight models are now serious options for high-sensitivity and data-sovereignty-important use cases. Self-hosted Llama 4 70B or DeepSeek V3 + good RAG architecture meets the quality bar for most enterprise use cases.
14. Outlook for 2027
- Open-closed gap shrinks to 5-8 points. If Meta's Llama 5 and DeepSeek V4 continue their 2025-2026 growth trajectory, they could catch up to flagships in 2027.
- Turkish weight grows. Anthropic and OpenAI low-resource language investments are improving Turkish fluency and domain coverage.
- Local model ecosystem consolidates. TÜBİTAK and major Turkish tech companies (Trendyol, Hepsiburada, Garanti BBVA) are investing in domain-specific Turkish models — vertical-specific, not general-purpose.
- Multimodal Turkish video/audio understanding standardizes. Gemini 3 + GPT-5 video iterations mature in 2026.
15. Frequently Asked Questions
16. Methodology Details
Scores were triangulated from three sources:
- Provider technical reports — OpenAI GPT-5 Technical Report, Anthropic Claude Opus 4.7 Card, Google Gemini 3 Tech Report. Turkish and general scores.
- Independent community benchmarks — Open LLM Leaderboard (Hugging Face), Stanford HELM, LMSYS Chatbot Arena (Turkish-supported).
- Enterprise project observations — anonymized performance data from 12+ active RAG/Agent projects in Turkey.
Limitations
- Turkish test sets are less mature than global ones. MMLU-TR and similar are translation-based; cultural-specific questions may be missing.
- Continuous-update challenge. Models change fast; this table is re-computed each quarter.
- Prompt-format effect. The same model can shift 5-10% on prompt-engineering choices; "best-prompt" principle applied.
17. Next Steps
To clarify the right Turkish LLM choice for your company:
- Model selection workshop. Use case, quality goal, cost budget, and compliance constraints reviewed in a 4-hour session. Output: 2-3 finalist models + eval plan.
- Comparison eval. Test candidate models on your own 30-100 question eval set; produce a concrete comparison report.
- Production deployment. Move the selected model into production with RAG + KVKK + observability for a Turkish enterprise.
Reach out via the contact form on the site.
References
- Open LLM Leaderboard — Hugging Face, Hugging Face ·
- MMLU: Measuring Massive Multitask Language Understanding — Hendrycks et al., ICLR ·
- Belebele: A Multilingual Reading Comprehension Benchmark — Bandarkar et al., arXiv ·
- TruthfulQA: Measuring How Models Mimic Human Falsehoods — Lin et al., ACL ·
- HumanEval: Evaluating Large Language Models Trained on Code — Chen et al., OpenAI ·
- MGSM: Multilingual Grade School Math — Shi et al., Google Research ·
- Stanford HELM Leaderboard — Stanford CRFM, Stanford University ·
- LMSYS Chatbot Arena — LMSYS, LMSYS ·
- Stanford AI Index Report 2025 — Stanford HAI, Stanford University ·
- State of AI Report 2025 — Benaich, N., Air Street Capital ·
This guide is updated quarterly. The URL remains permanent for the 2027 edition; check the "Last updated" header at the top.
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