Claude Sonnet 4.5 vs GLM 5.3 Flash
At a Glance
| Compare | Claude Sonnet 4.5Anthropic |  GLM 5.3 FlashZ.ai |
|---|---|---|
| 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 | #29 of 4654.6 score · 2/3 sources · provisional · missing ARC-AGI-2 · full-core range 36.4–69.8 |
| CostLower is better · Published-token output estimate | UnrankedNot in the 44-model eligible cohort | #2 of 44$0.0087 per LiveBench case |
| EfficiencyHigher is better · MM Efficiency v1.5 | UnrankedNot in the 38-model eligible cohort | #1 of 3877.3 score · 2/3 sources · provisional · missing ARC-AGI-2 · full-core range 68.2–84.9 |
| Pricing and Limits | ||
| Input priceFrom · USD / 1M tokens | $3.00Anthropic ↗ · Sep 3, 2026 | $0.075Z.ai ↗ · Aug 29, 2026 |
| Output priceFrom · USD / 1M tokens | $15.00Anthropic ↗ · Sep 3, 2026 | $0.25Z.ai ↗ · Aug 29, 2026 |
| Context windowMaximum documented tokens | 200K | 1,000K |
| Model facts checked | Sep 3, 2026View model evidence → | Sep 2, 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
| Benchmark | Claude Sonnet 4.5 | GLM-5.3-Flash |
|---|---|---|
| LMArena Text Arenatext-2026-09-13-d25aabda0010 · arena_rating · leader | 1,433.9497% of row best · rating · claude-sonnet-4-5-20250929-high-32k; 95% CI [1431.13982742, 1436.74901697]; votes 80980; rank 81 | 1,471.89100% of row best · rating · glm-5.3-flash; 95% CI [1465.37026588, 1478.41920488]; votes 10038; rank 24 |
| ToneBench2026-09-11-10-task-4ef099199c9c · overall_score · unverified | 77.2588% of row best · points · Claude Sonnet 4.5 · 7,415 output tokens / case | 88.19100% of row best · points · GLM-5.3 Flash · 25,960 output tokens / case |
| Overall ResultCounted from the protocol-matched rows above | 0 benchmark winsNo overall winner | 1 benchmark winNo overall winner |
Third-party benchmark Only like-for-like primary-publisher results are shown; raw scores, relative scores, configuration, and token spend remain visible.
Side-by-Side Facts
| Field | Claude Sonnet 4.5 | GLM-5.3-Flash |
|---|---|---|
| Developer | Anthropic | Z.ai |
| Family | Claude 4 | Glm 5 3 Flash |
| Model | Claude Sonnet 4.5 | GLM-5.3-Flash |
| Version | Claude Sonnet 4.5 | GLM-5.3-Flash |
| Lifecycle | active | active |
| Released | 2025-09-29 | 2026-09-02 |
| Knowledge cutoff | 2025-01-01 | Unknown |
| Input modalities | Text, Image | Text, Image, Video, Document |
| Output modalities | Text | Text |
| Context window | 200K | 1,000K |
| Total parameters | Unknown | 320B |
| Active parameters | Unknown | 18B |
| License | Unknown | MIT |
| Open weights | No | Yes |
| API available | Yes | Yes |
| Self-hostable | No | Yes |
| Provider access | Anthropic (Standard) | Deepinfra (Standard), Fireworks Ai (Standard), Together Ai (Standard), Z.ai (Standard) |
| Capabilities | chat, generation, reasoning, structured_outputs, tools | agents, chat, computer-use, reasoning, structured_outputs, tools, vision |
Claude Sonnet 4.5 Capabilities
GLM 5.3 Flash Capabilities
Related Comparisons
All image comparisons →| A | Pair | B | Context |
|---|---|---|---|
Claude Sonnet 4.5Anthropic | vs |  GPT-6 AstraOpenAI | cross-developer peersimage, text |
Claude Fable 5.1Anthropic | vs | Claude Sonnet 4.5Anthropic | family variantsimage, text |
Claude Sonnet 4.5Anthropic | vs |  Gemini 3.1 ProGoogle DeepMind | cross-developer peerstext |
Claude Sonnet 4.5Anthropic | vs |  DeepSeek-V4.1-FlashDeepSeek | cross-developer peersimage, text |
Claude Sonnet 4.5Anthropic | vs | Grok 4.6xAI | cross-developer peersimage, text |
Claude Sonnet 4.5Anthropic | vs |  Qwen3.8-MaxQwen | cross-developer peersimage, text |
Claude Sonnet 4.5Anthropic | vs |  Kimi-K3Moonshot AI | cross-developer peersimage, text |
 MiniMax-M3MiniMax | vs | Claude Sonnet 4.5Anthropic | cross-developer peersimage, text |
Claude Sonnet 4.5Anthropic | vs | GLM-5.3Z.ai | cross-developer peerstext |
Claude Sonnet 4.5Anthropic | vs |  Hy4 previewTencent | cross-developer peerstext |
Claude Sonnet 4.5Anthropic | vs | Seed 2.1 ProByteDance Seed | cross-developer peersimage, text |
Claude Sonnet 4.5Anthropic | vs |  Mistral Large 3Mistral AI | cross-developer peersimage, text |
Primary Evidence
Sources and Freshness
Questions
Claude Sonnet 4.5 vs GLM 5.3 Flash FAQs
Is Claude Sonnet 4.5 or GLM 5.3 Flash better for coding?+
This comparison does not currently contain a protocol-matched coding benchmark for both Claude Sonnet 4.5 and GLM 5.3 Flash, so Model Markets cannot name a coding leader from pricing, context size, or capability labels alone.
Which is cheaper, Claude Sonnet 4.5 or GLM 5.3 Flash?+
Claude Sonnet 4.5 is $3.00 and GLM 5.3 Flash is $0.075 per million tokens, so GLM 5.3 Flash is cheaper on this metric. Claude Sonnet 4.5 is $15.00 and GLM 5.3 Flash is $0.25 per million tokens, so GLM 5.3 Flash is cheaper on this metric.
Which has a larger context window, Claude Sonnet 4.5 or GLM 5.3 Flash?+
GLM 5.3 Flash has the larger sourced context window. Claude Sonnet 4.5 supports 200K and GLM 5.3 Flash supports 1,000K.
Which performs better in benchmarks, Claude Sonnet 4.5 or GLM 5.3 Flash?+
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 GLM 5.3 Flash be self-hosted?+
GLM 5.3 Flash is the only model in this pair currently marked as self-hostable. Claude Sonnet 4.5 is not marked open weight; GLM 5.3 Flash is open weight.
Can Claude Sonnet 4.5 and GLM 5.3 Flash understand images?+
Claude Sonnet 4.5 is documented with image input; GLM 5.3 Flash is documented with image input. This reflects supported input modalities, not vision quality.
Which can generate longer answers, Claude Sonnet 4.5 or GLM 5.3 Flash?+
GLM 5.3 Flash has the larger sourced maximum output: Claude Sonnet 4.5 supports 64K and GLM 5.3 Flash supports 131K output tokens.
Do Claude Sonnet 4.5 and GLM 5.3 Flash support reasoning and tool use?+
Claude Sonnet 4.5: reasoning, tool calling, and image input. GLM 5.3 Flash: reasoning, tool calling, and image input. Feature support does not establish relative quality.
Which is available from more inference providers, Claude Sonnet 4.5 or GLM 5.3 Flash?+
Claude Sonnet 4.5 has 1 sourced provider route; GLM 5.3 Flash has 4, so GLM 5.3 Flash has broader tracked availability.
Which offers better value, Claude Sonnet 4.5 or GLM 5.3 Flash?+
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.