# BTL-4 vs Solar Open 2

> Side-by-side benchmark comparison for BTL-4 and Solar Open 2 across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/btl-4-vs-solar-open-2
- Last updated: September 10, 2026

- Shared sourced benchmarks: 2
- HTML indexing: indexable
- Ranking lane: BenchAlign v5

## Quick Verdict

Evidence is too thin for a benchmark verdict: BTL-4 and Solar Open 2 share only 2 sourced benchmark rows.

## Summary

- Only 2 shared sourced benchmark rows are available. That is not enough for a broad capability verdict, so this mirror does not name an overall winner.
- Solar Open 2 has the larger published context window at 1M.

## Model Snapshot

| Property | BTL-4 | Solar Open 2 |
|----------|----------|----------|
| Creator | Bad Theory Labs | Upstage |
| Type | Open Weight | Open Weight |
| Reasoning | Reasoning | Reasoning |
| Context | 262K | 1M |
| Independent public score (not head-to-head) | null | null |
| Benchmarks Covered | 3 | 11 |
| Pricing (input/output) | $0.00 / $0.00 | $0.00 / $0.00 |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- BTL-4 public-lane score: 49.9 (Estimated · #57/152)
- Solar Open 2 public-lane score: Coming soon

| Benchmark | BTL-4 | Solar Open 2 | Winner |
|-----------|-----------|-----------|--------|
| BFCL v4 | 73.5% | Coming soon | Coming soon |
| terminalBenchHard | Coming soon | 28.3% | Coming soon |
| APEX-Agents | Coming soon | 16.6% | Coming soon |
| MCP Atlas | Coming soon | 58.2% | Coming soon |

### Coding

- Winner: Insufficient shared evidence
- BTL-4 public-lane score: 49.8 (Estimated · #62/151)
- Solar Open 2 public-lane score: Coming soon

| Benchmark | BTL-4 | Solar Open 2 | Winner |
|-----------|-----------|-----------|--------|
| SWE-bench Verified | 78.4% | 70.4% | BTL-4 |
| LiveCodeBench v6 | 66.1% | 92.4% | Solar Open 2 |

### Knowledge

- Winner: Insufficient shared evidence
- BTL-4 public-lane score: Coming soon
- Solar Open 2 public-lane score: Coming soon

| Benchmark | BTL-4 | Solar Open 2 | Winner |
|-----------|-----------|-----------|--------|
| MMLU-Pro | Coming soon | 86.2% | Coming soon |
| GPQA-D | Coming soon | 86.3% | Coming soon |
| HLE w/o tools | Coming soon | 28.8% | Coming soon |

### Instruction Following

- Winner: Insufficient shared evidence
- BTL-4 public-lane score: Coming soon
- Solar Open 2 public-lane score: Coming soon

| Benchmark | BTL-4 | Solar Open 2 | Winner |
|-----------|-----------|-----------|--------|
| IFBench | Coming soon | 80% | Coming soon |

### Mathematics

- Winner: Insufficient shared evidence
- BTL-4 public-lane score: Coming soon
- Solar Open 2 public-lane score: Coming soon

| Benchmark | BTL-4 | Solar Open 2 | Winner |
|-----------|-----------|-----------|--------|
| HMMT Feb 2026 | Coming soon | 93.9% | Coming soon |
| AIME26 | Coming soon | 95.7% | Coming soon |

## FAQ

### Is there enough evidence to pick between BTL-4 and Solar Open 2?

Not yet. The models share only 2 sourced benchmark rows, so this mirror reports the available measurements and metadata without naming a broad winner.

### What can I compare safely on this page?

Published pricing, context windows, model type, and individual shared benchmark rows are directly comparable. Independent overall scores and non-overlapping benchmark coverage are labeled separately and should not be read as a controlled head-to-head result.

## Related Comparisons

- [BTL-4 vs BTL-3](/compare/btl-3-vs-btl-4)
- [Solar Open 2 vs BTL-3](/compare/btl-3-vs-solar-open-2)
- [BTL-4 vs BTL-4 Compact](/compare/btl-4-vs-btl-4-compact)
- [Solar Open 2 vs BTL-4 Compact](/compare/btl-4-compact-vs-solar-open-2)

## Explore More

- [BTL-4 profile](/models/btl-4)
- [Solar Open 2 profile](/models/solar-open-2)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)