Claude Sonnet 4.5 vs FLUX.2 klein 4B FP8
At a Glance
| Compare | Claude Sonnet 4.5Anthropic |  FLUX.2 klein 4B FP8Black Forest Labs |
|---|---|---|
| Intelligence, Cost, and Efficiency | ||
| IntelligenceHigher is better · MM Intelligence v2.5 | #36 of 4627.7 score · 2/3 sources · provisional · missing LiveBench · full-core range 18.5–51.8 | UnrankedNot in the 46-model eligible cohort |
| Pricing and Limits | ||
| Input priceFrom · USD / 1M tokens | $3.00Anthropic ↗ · Sep 3, 2026 | Not reported |
| Output priceFrom · USD / 1M tokens | $15.00Anthropic ↗ · Sep 3, 2026 | Not reported |
| Context windowMaximum documented tokens | 200K | Not reported |
| Model facts checked | Sep 3, 2026View model evidence → | Aug 28, 2026View model evidence → |
Token prices are the lowest available sourced USD rates; input and output may use different providers. Cost ranking estimates output spend on LiveBench, not a full request bill. Ranking methodology →
Available Benchmarks
Side-by-Side Facts
| Field | Claude Sonnet 4.5 | FLUX.2-klein-4b-fp8 |
|---|---|---|
| Developer | Anthropic | Black Forest Labs |
| Family | Claude 4 | Flux 2 Klein 4b Fp8 |
| Model | Claude Sonnet 4.5 | FLUX.2-klein-4b-fp8 |
| Version | Claude Sonnet 4.5 | FLUX.2-klein-4b-fp8 |
| Lifecycle | active | active |
| Released | 2025-09-29 | 2026-01-15 |
| Knowledge cutoff | 2025-01-01 | Unknown |
| Input modalities | Text, Image | Image |
| Output modalities | Text | Image |
| Context window | 200K | Unknown |
| Total parameters | Unknown | 4B |
| Active parameters | Unknown | Unknown |
| License | Unknown | apache-2.0 |
| Open weights | No | Yes |
| API available | Yes | Unknown |
| Self-hostable | No | Yes |
| Provider access | Anthropic (Standard) | Unknown |
| Capabilities | chat, generation, reasoning, structured_outputs, tools | generation |
Claude Sonnet 4.5 Capabilities
FLUX.2 klein 4B FP8 Capabilities
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Primary Evidence
Sources and Freshness
Questions
Claude Sonnet 4.5 vs FLUX.2 klein 4B FP8 FAQs
Is Claude Sonnet 4.5 or FLUX.2 klein 4B FP8 better for coding?+
This comparison does not currently contain a protocol-matched coding benchmark for both Claude Sonnet 4.5 and FLUX.2 klein 4B FP8, so Model Markets cannot name a coding leader from pricing, context size, or capability labels alone.
Which is cheaper, Claude Sonnet 4.5 or FLUX.2 klein 4B FP8?+
Only Claude Sonnet 4.5 has a directly sourced input price: $3.00 per million tokens. Only Claude Sonnet 4.5 has a directly sourced output price: $15.00 per million tokens.
Which has a larger context window, Claude Sonnet 4.5 or FLUX.2 klein 4B FP8?+
Neither model has a larger sourced context window in this comparison. Claude Sonnet 4.5 is 200K and FLUX.2 klein 4B FP8 is —.
Which performs better in benchmarks, Claude Sonnet 4.5 or FLUX.2 klein 4B FP8?+
There is no overall benchmark winner: At least two independently verified, protocol-matched benchmarks are required for an overall winner.
Can Claude Sonnet 4.5 or FLUX.2 klein 4B FP8 be self-hosted?+
FLUX.2 klein 4B FP8 is the only model in this pair currently marked as self-hostable. Claude Sonnet 4.5 is not marked open weight; FLUX.2 klein 4B FP8 is open weight.
Can Claude Sonnet 4.5 and FLUX.2 klein 4B FP8 understand images?+
Claude Sonnet 4.5 is documented with image input; FLUX.2 klein 4B FP8 is documented with image input. This reflects supported input modalities, not vision quality.
Which can generate longer answers, Claude Sonnet 4.5 or FLUX.2 klein 4B FP8?+
Neither has a larger sourced maximum output. Claude Sonnet 4.5 is 64K and FLUX.2 klein 4B FP8 is —.
Do Claude Sonnet 4.5 and FLUX.2 klein 4B FP8 support reasoning and tool use?+
Claude Sonnet 4.5: reasoning, tool calling, and image input. FLUX.2 klein 4B FP8: image input. Feature support does not establish relative quality.
Which is available from more inference providers, Claude Sonnet 4.5 or FLUX.2 klein 4B FP8?+
Claude Sonnet 4.5 has 1 sourced provider route; FLUX.2 klein 4B FP8 has 0, so Claude Sonnet 4.5 has broader tracked availability.
Which offers better value, Claude Sonnet 4.5 or FLUX.2 klein 4B FP8?+
There is no universal value winner. Compare the input and output prices above with the matched benchmark result for your workload: cheaper tokens can be offset by different quality, token usage, latency, or provider availability.