# Claude Sonnet 5.5 vs Reka Flash 3

> Claude Sonnet 5.5 has enough public results to be ranked (#10); Reka Flash 3 does not yet, so treat this comparison as directional.

- Canonical page: https://noometry.com/compare/claude-sonnet-5-5-vs-reka-flash-3
- Last updated: 2026-10-10
- Shared benchmarks: 0

## Summary

- The widest gap is in agentic & tool use, where Claude Sonnet 5.5 leads 44.9 to 30.1.
- Reka Flash 3 is cheaper at $0.10 / $0.20 per million input/output tokens, against $2 / $10 for Claude Sonnet 5.5.
- Claude Sonnet 5.5 accepts more context: 1M tokens versus 66K.
- Reka Flash 3 has downloadable open weights; the other is API-only.

## Snapshot

| | Claude Sonnet 5.5 | Reka Flash 3 |
|---|---|---|
| Provider | Anthropic | Reka |
| Noometry Index | 60.5 | 36.4 |
| Rank | 10 | — |
| Context | 1M | 66K |
| Input $/M | $2 | $0.10 |
| Output $/M | $10 | $0.20 |
| Weights | Proprietary | Open |

## Coding

- Claude Sonnet 5.5: 65.5 (#6)
- Reka Flash 3: —

| Benchmark | Claude Sonnet 5.5 | Reka Flash 3 |
|---|---|---|
| FrontierCode | 52.1% | — |
| CursorBench | 55.5% | — |
| LMArena WebDev | 1699 | — |
| FrontierSWE | 61.9% | — |
| SciCode | 61% | — |
| ALE-Bench | 1,819 | — |

## Agentic & Tool Use

- Claude Sonnet 5.5: 44.9 (#14)
- Reka Flash 3: 30.1

| Benchmark | Claude Sonnet 5.5 | Reka Flash 3 |
|---|---|---|
| APEX-Agents | 75.5% | — |
| BALROG | — | 29.2% |

## Reasoning

- Claude Sonnet 5.5: 52.4 (#29)
- Reka Flash 3: —

| Benchmark | Claude Sonnet 5.5 | Reka Flash 3 |
|---|---|---|
| CritPt | 31.4% | — |
| Mystery Game Puzzles | 65% | — |

## Math

- Claude Sonnet 5.5: 88.7 (#4)
- Reka Flash 3: —

| Benchmark | Claude Sonnet 5.5 | Reka Flash 3 |
|---|---|---|
| FrontierMath (Tiers 1-3) | 88.8% | — |
| FrontierMath Tier 4 | 80.5% | — |
| OTIS Mock AIME 2024-2025 | 100% | — |
| ProofBench | 100% | — |

## Knowledge

- Claude Sonnet 5.5: 66.0 (#11)
- Reka Flash 3: —

| Benchmark | Claude Sonnet 5.5 | Reka Flash 3 |
|---|---|---|
| GPQA Diamond | 95.6% | — |
| SimpleQA Verified | 46.5% | — |

## Multimodal

- Claude Sonnet 5.5: 53.2 (#5)
- Reka Flash 3: —

| Benchmark | Claude Sonnet 5.5 | Reka Flash 3 |
|---|---|---|
| Furniture Assembly | 75% | — |

## Writing & Preference

- Claude Sonnet 5.5: —
- Reka Flash 3: 43.8

| Benchmark | Claude Sonnet 5.5 | Reka Flash 3 |
|---|---|---|
| EQ-Bench Creative Writing | — | 1228 |

## FAQ

### Is Claude Sonnet 5.5 better than Reka Flash 3?

Claude Sonnet 5.5 has enough public results to be ranked (#10); Reka Flash 3 does not yet, so treat this comparison as directional.

### Which is cheaper, Claude Sonnet 5.5 or Reka Flash 3?

Reka Flash 3 is cheaper. It lists at $0.10 per million input tokens and $0.20 per million output tokens; Claude Sonnet 5.5 lists at $2 and $10.

### Which has the bigger context window?

Claude Sonnet 5.5 does, with 1M tokens against 66K.

### How many benchmarks do Claude Sonnet 5.5 and Reka Flash 3 share?

0 benchmarks have published results for both models. Claude Sonnet 5.5 has 16 scored results on Noometry and Reka Flash 3 has 2.