Model comparison
GPT-5.5 Pro vs Laguna S 2.1
Head-to-head evidence from 0 shared benchmark results across 0 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: GPT-5.5 Pro #38 (Estimated); Laguna S 2.1 unranked (Not scored). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. GPT-5.5 Pro and Laguna S 2.1 share 0 comparable benchmark results. 1 of 8 categories are comparable. 7 results are unique to GPT-5.5 Pro; 6 to Laguna S 2.1.
Updated July 21, 2026- Shared results
- 0
- GPT-5.5 Pro only
- 7
- Laguna S 2.1 only
- 6
- Comparable categories
- 1 / 8
Treat this as a split decision. GPT-5.5 Pro makes more sense if agentic is the priority; Laguna S 2.1 is the better fit if you want the cheaper token bill.
Confidence note. This is a partial-evidence comparison with 0 shared benchmark results across 0 evidence categories; 1 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
GPT-5.5 Pro and Laguna S 2.1 finish on the same BenchAlign overall score, so this is less about a single winner and more about where the edge shows up. The BenchAlign headline says tie; the benchmark table is where the real choice happens.
GPT-5.5 Pro is also the more expensive model on tokens at $30.00 input / $180.00 output per 1M tokens, versus $0.10 input / $0.20 output per 1M tokens for Laguna S 2.1. That is roughly 900.0x on output cost alone.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | GPT-5.5 Pro | Laguna S 2.1 | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | GPT-5.5 Pro$30 input / $180 output | Laguna S 2.1$0.1 input / $0.2 output | Laguna S 2.1 has the lower combined listed price. |
| Generation speedtokens per second | GPT-5.5 ProNot available | Laguna S 2.1Not available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | GPT-5.5 ProNot available | Laguna S 2.1Not available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | GPT-5.5 Pro1M | Laguna S 2.11M | Listed context windows are equal. |
Benchmark Deep Dive
AgenticGPT-5.5 Pro wins3 benchmarks
Coding4 benchmarks
Reasoning1 benchmarks
| Benchmark | GPT-5.5 Pro | Laguna S 2.1 | Result |
|---|---|---|---|
| CritPtSource | 30.6% | — | Not comparable |
Knowledge2 benchmarks
Frequently Asked Questions (2)
Which is better, GPT-5.5 Pro or Laguna S 2.1?
GPT-5.5 Pro and Laguna S 2.1 are tied on the BenchAlign overall score, so the right pick depends on which category matters most for your use case.
Which is better for agentic tasks, GPT-5.5 Pro or Laguna S 2.1?
GPT-5.5 Pro has the edge for agentic tasks in this comparison, averaging 90.1 versus 70.2. Laguna S 2.1 stays close enough that the answer can still flip depending on your workload.
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