Claude Fable 5.1 vs GLM 5.3 Flash
At a Glance
| Compare | Claude Fable 5.1Anthropic |  GLM 5.3 FlashZ.ai |
|---|---|---|
| Intelligence, Cost, and Efficiency | ||
| IntelligenceHigher is better · MM Intelligence v2.5 | #1 of 4699.0 score · 3/3 sources · complete | #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 | #43 of 44$0.824 per LiveBench case | #2 of 44$0.0087 per LiveBench case |
| EfficiencyHigher is better · MM Efficiency v1.5 | #22 of 3851.7 score · 3/3 sources · complete | #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 | $10.00Anthropic ↗ · Sep 3, 2026 | $0.075Z.ai ↗ · Aug 29, 2026 |
| Output priceFrom · USD / 1M tokens | $50.00Anthropic ↗ · Sep 3, 2026 | $0.25Z.ai ↗ · Aug 29, 2026 |
| Context windowMaximum documented tokens | 1,000K | 1,000K |
| Model facts checked | Sep 2, 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 Fable 5.1 | GLM-5.3-Flash |
|---|---|---|
| LMArena Agent Arenaagent-2026-09-15-d25aabda0010 · outcome_score · leader | 13.71100% of row best · score · Claude Fable 5.1 (Max); 95% CI [11.98654915, 15.42403622]; sessions 13320; observations 1453463; rank 1 | 1.1589% of row best · score · GLM 5.3 Flash; 95% CI [0.48275443, 1.81278415]; sessions 43164; observations 4433017; rank 25 |
| LMArena Text Arenatext-2026-09-13-d25aabda0010 · arena_rating · leader | 1,507.58100% of row best · rating · claude-fable-5.1-max; 95% CI [1499.42882565, 1515.73467375]; votes 5783; rank 1 | 1,471.8998% of row best · rating · glm-5.3-flash; 95% CI [1465.37026588, 1478.41920488]; votes 10038; rank 24 |
| LMArena Vision Arenavision-2026-09-13-d25aabda0010 · arena_rating · statistical tie | 1,322.34100% of row best · rating · claude-fable-5.1-max; 95% CI [1310.08723910, 1334.59344910]; votes 2701; rank 2 | 1,298.7198% of row best · rating · glm-5.3-flash; 95% CI [1287.06707337, 1310.34654848]; votes 3110; rank 17 |
| LiveBench2026-06-25 · overall · leader | 86.82100% of row best · percent · claude-fable-5-1-max-effort · 16,470 output tokens / case | 73.2784% of row best · percent · glm-5.3-flash · 34,707 output tokens / case |
| ToneBench2026-09-11-10-task-4ef099199c9c · overall_score · unverified | 89.71100% of row best · points · Claude Fable 5.1 (max effort) · 60,786 output tokens / case | 88.1998% of row best · points · GLM-5.3 Flash · 25,960 output tokens / case |
| Overall ResultCounted from the protocol-matched rows above · 1 tie | 3 benchmark winsOverall lead | 0 benchmark wins |
Third-party benchmark Only like-for-like primary-publisher results are shown; raw scores, relative scores, configuration, and token spend remain visible.
Quality Versus Estimated Output Cost
Side-by-Side Facts
| Field | Claude Fable 5.1 | GLM-5.3-Flash |
|---|---|---|
| Developer | Anthropic | Z.ai |
| Family | Claude 5 1 | Glm 5 3 Flash |
| Model | Claude Fable 5.1 | GLM-5.3-Flash |
| Version | Claude Fable 5.1 | GLM-5.3-Flash |
| Lifecycle | active | active |
| Released | 2026-09-01 | 2026-09-02 |
| Knowledge cutoff | 2026-06-01 | Unknown |
| Input modalities | Text, Image | Text, Image, Video, Document |
| Output modalities | Text | Text |
| Context window | 1,000K | 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, tools | agents, chat, computer-use, reasoning, structured_outputs, tools, vision |
Claude Fable 5.1 Capabilities
GLM 5.3 Flash Capabilities
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Primary Evidence
Sources and Freshness
Questions
Claude Fable 5.1 vs GLM 5.3 Flash FAQs
Is Claude Fable 5.1 or GLM 5.3 Flash better for coding?+
This comparison does not currently contain a protocol-matched coding benchmark for both Claude Fable 5.1 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 Fable 5.1 or GLM 5.3 Flash?+
Claude Fable 5.1 is $10.00 and GLM 5.3 Flash is $0.075 per million tokens, so GLM 5.3 Flash is cheaper on this metric. Claude Fable 5.1 is $50.00 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 Fable 5.1 or GLM 5.3 Flash?+
Neither model has a larger sourced context window in this comparison. Claude Fable 5.1 is 1,000K and GLM 5.3 Flash is 1,000K.
Which performs better in benchmarks, Claude Fable 5.1 or GLM 5.3 Flash?+
Claude Fable 5.1 leads the current overall benchmark count. The result uses 4 protocol-matched benchmarks from 2 publishers; it is not a universal quality score.
Can Claude Fable 5.1 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 Fable 5.1 is not marked open weight; GLM 5.3 Flash is open weight.
Can Claude Fable 5.1 and GLM 5.3 Flash understand images?+
Claude Fable 5.1 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 Fable 5.1 or GLM 5.3 Flash?+
GLM 5.3 Flash has the larger sourced maximum output: Claude Fable 5.1 supports 128K and GLM 5.3 Flash supports 131K output tokens.
Do Claude Fable 5.1 and GLM 5.3 Flash support reasoning and tool use?+
Claude Fable 5.1: 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 Fable 5.1 or GLM 5.3 Flash?+
Claude Fable 5.1 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 Fable 5.1 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.