Claude Opus 4.6 vs GPT-5.2
Claude Opus 4.6 (Anthropic, released Feb 2026) and GPT-5.2 (OpenAI, released Dec 2025) are both frontier models built for agentic and coding workloads. Opus 4.6 pushes context to 1M tokens and posts consistently higher Design Arena rankings across coding and agent categories. GPT-5.2 counters with a lower price and a 400K context window that's still large enough for most real codebases. Both run on OpenKey with one key and a flat 3% fee over provider list price.
Spec vs spec
| Spec | Claude Opus 4.6 | GPT-5.2 |
|---|---|---|
| Context window | 1M | 400K |
| Max output | 128K | 128K |
| Input modalities | text, image, file | file, image, text |
| Output modalities | text | text |
| Released | Feb 4, 2026 | Dec 10, 2025 |
| Reasoning | optional | optional |
Pricing
Per 1M tokens. Provider price plus the flat 3% fee — the sum is what you pay.
anthropic/claude-opus-4.6
Input · 1M tokens
$5.00 + 3%$5.15
Output · 1M tokens
$25.00 + 3%$25.75
Cache read · 1M tokens
$0.500 + 3%$0.515
Cache write · 1M tokens
$6.25 + 3%$6.44
FEE — FLAT, EVERY MODEL3%
openai/gpt-5.2
Input · 1M tokens
$1.75 + 3%$1.80
Output · 1M tokens
$14.00 + 3%$14.42
Cache read · 1M tokens
$0.175 + 3%$0.180
FEE — FLAT, EVERY MODEL3%
One workload, priced on both
10M input + 2M output tokens at each model's price, flat 3% fee included.
anthropic/claude-opus-4.6
$103.00
$100.00 provider + 3%
openai/gpt-5.2Cheaper
$46.87
$45.50 provider + 3%
Benchmarks
Design Arena categories where both models have results. Higher Elo and lower rank win.
| Claude Opus 4.6 | GPT-5.2 | |||
|---|---|---|---|---|
| Category | Elo | Rank | Elo | Rank |
| 3D | 1351 | #4 | 1156 | #60 |
| androidnative | 1216 | #11 | 1074 | #22 |
| ASCII art | 1307 | #6 | 1199 | #22 |
| Code | 1342 | #3 | 1219 | #42 |
| Data viz | 1322 | #5 | 1245 | #31 |
| Full-stack | 1288 | #4 | 1110 | #21 |
| Game dev | 1344 | #4 | 1260 | #29 |
| Mobile apps | 1261 | #3 | 1173 | #23 |
| SVG | 1288 | #4 | 1197 | #31 |
| UI components | 1350 | #3 | 1243 | #32 |
| Web apps | 1266 | #4 | 1156 | #19 |
| Websites | 1338 | #3 | 1237 | #34 |
Head-to-head preference voting. How we filter and rank
Pricing math on a real workload
On OpenKey, Opus 4.6 costs $5.15/M input and $25.75/M output ($5.00 and $25.00 provider price x 1.03). GPT-5.2 costs $1.8025/M input and $14.42/M output ($1.75 and $14.00 x 1.03). Run the numbers on a 10M-input / 2M-output workload: Opus 4.6 comes to $100.00, GPT-5.2 comes to $45.50. That's a 2.86x gap on input pricing and roughly 2.2x on this specific workload total. If you're running this at scale — thousands of calls a day — that difference compounds fast. GPT-5.2 is the default choice unless you have a specific reason to pay for Opus 4.6's benchmark edge.
Coding and agent benchmarks
Design Arena data is one-sided here. In the agents arena, Opus 4.6 ranks 3rd-11th across androidnative, fullstack, mobileapps, and webapps categories (elo 1216-1288). GPT-5.2 ranks 13th-23rd on the same categories (elo 1074-1183). The gap holds in the models arena too: Opus 4.6 hits rank 3 on uicomponent (elo 1350) and codecategories (elo 1342), while GPT-5.2's best model-arena finish is rank 22 on asciiart (elo 1199). If your workload is agentic coding — multi-step tasks, tool calls, full-stack builds — Opus 4.6's win rates are meaningfully higher across the board, not just on one category.
Context and long-document work
Opus 4.6 supports a 1,000,000-token context window; GPT-5.2 caps at 400,000 — a 2.5x gap. Both cap max completion output at 128,000 tokens, so the difference only matters on the input side: large codebases, long transcripts, or multi-document retrieval. For most day-to-day agent work, 400K is still plenty. Reach for Opus 4.6 specifically when you're feeding it an entire repo or a document set that would get truncated at 400K tokens.
Modality and tooling
Both models accept text, image, and file input and return text-only output — no functional modality difference here. They diverge on reasoning controls: Opus 4.6 exposes four effort levels (max, high, medium, low) plus `top_k` and `verbosity` parameters; GPT-5.2 exposes five levels including `xhigh` and `none`, plus a `seed` parameter for reproducibility. If deterministic output matters to your pipeline, GPT-5.2's seed support is the more direct lever. If you want manual control over reasoning depth including a hard ceiling (`max`), Opus 4.6 gives you that.
Which model for which job
| Use case | Pick | Why |
|---|---|---|
| Full-stack agent coding | Claude Opus 4.6 | Rank 4 vs rank 21 in Design Arena's fullstack agent category |
| High-volume API workload on a budget | GPT-5.2 | $45.50 vs $100 for a 10M-input/2M-output run |
| Whole-repo or long-document analysis | Claude Opus 4.6 | 1M token context vs GPT-5.2's 400K, a 2.5x difference |
| UI component generation | Claude Opus 4.6 | Rank 3 (elo 1350) vs GPT-5.2's rank 32 (elo 1243) |
| Reproducible, deterministic output | GPT-5.2 | Supports a `seed` parameter; Opus 4.6 does not expose one |
| Web app generation | Claude Opus 4.6 | Rank 4 (elo 1266, 60.9% win rate) vs GPT-5.2 rank 19 (elo 1156, 45.7%) |
Questions
- Is Claude Opus 4.6 or GPT-5.2 cheaper?
- GPT-5.2 is cheaper on every metric: $1.8025/M input and $14.42/M output on OpenKey vs Opus 4.6's $5.15/M input and $25.75/M output. On a 10M-input/2M-output workload, that's $45.50 for GPT-5.2 versus $100.00 for Opus 4.6.
- Which model has a bigger context window?
- Claude Opus 4.6 supports 1,000,000 tokens of context, 2.5x GPT-5.2's 400,000-token window. Both cap output at 128,000 tokens, so the gap only matters for large inputs like full repositories or long document sets.
- Which model is better for coding agents?
- Claude Opus 4.6, based on Design Arena data. It ranks 4th in fullstack (elo 1288, 68.6% win rate) and 4th in webapps (elo 1266), while GPT-5.2 ranks 21st and 19th respectively in the same categories.
- Can I use both models with one API key?
- Yes. Both Claude Opus 4.6 and GPT-5.2 are available on OpenKey with a single API key across all 329 models on the platform, priced at provider list price plus a flat 3% fee.