Claude Fable 5.1 vs GLM 5.3 Flash
API pricing, context window and capabilities for Claude Fable 5.1 and GLM 5.3 Flash, side by side. Prices are the cheapest listed serving route per 1M tokens, from LiteLLM and OpenRouter.
Verdict
computed from the published numbersClaude Fable 5.1 wins on Terminal-Bench and on intelligence. GLM 5.3 Flash wins on price.
Price
GLM 5.3 Flash
Terminal-Bench
Claude Fable 5.1
Intelligence
Claude Fable 5.1
Context window
Tied
Key takeaways
who wins on what, from the published numbersClaude Fable 5.1 wins
- Has web search
GLM 5.3 Flash wins
- Cheaper input ($10.00 vs $0.11 /1M)
- Cheaper output ($50.00 vs $0.35 /1M)
- Higher max output (128K vs 1M)
- More serving providers (7 vs 13)
Cheaper overall
GLM 5.3 Flash
$0.11 + $0.35 /1M
Larger context
Tied
More providers
GLM 5.3 Flash
13 providers
Pricing & specs
cheapest listed route · per 1M tokensOn-demand listed rates, OpenRouter routed quotes and Vercel reseller quotes. Enterprise commitments can be materially lower.
| Claude Fable 5.1 | GLM 5.3 Flash | |
|---|---|---|
| Input $/1M | $10.00via Anthropic | $0.11via Sail best |
| Output $/1M | $50.00via Anthropic | $0.35via Sail best |
| Context window | 1M | 1M |
| Max output | 128K | 1M best |
| Serving providers | 7 | 13 best |
| Date | Released Sep 1, 2026 | Released Aug 26, 2026 |
Benchmarks
Benchmark scores, side by side| Claude Fable 5.1 | GLM 5.3 Flash | |
|---|---|---|
| Intelligence | 53.4 best | 41.8 |
| Terminal-Bench | 91% best | 84% |
| GPQA Diamond | 94% best | 91% |
| Output speed | 71 t/s best | 67 t/s |
| Latency (TTFT) | 249.68s | 2.80s best |
Cost calculator
choose a serving route for each sideInput tokens / month
Output tokens / month
Claude Fable 5.1
via Amazon Bedrock
$100
GLM 5.3 Flash
via Sail
$0.90
Capabilities
feature support, side by side| Feature | Claude Fable 5.1 | GLM 5.3 Flash |
|---|---|---|
| Vision | ✓ | ✓ |
| Tool use | ✓ | ✓ |
| Reasoning | ✓ | ✓ |
| Audio | — | — |
| Prompt caching | ✓ | ✓ |
| Structured output | ✓ | ✓ |
| Web search | ✓ | — |
Related comparisons
Frequently asked questions
Which is cheaper, Claude Fable 5.1 or GLM 5.3 Flash?
GLM 5.3 Flash is cheaper for input ($10.00 vs $0.11 per 1M tokens) from Sail. GLM 5.3 Flash is cheaper for output ($50.00 vs $0.35 per 1M tokens) from Sail.
What is the context window difference between Claude Fable 5.1 and GLM 5.3 Flash?
Both Claude Fable 5.1 and GLM 5.3 Flash have about a 1M-token context window.
How do Claude Fable 5.1 and GLM 5.3 Flash compare on benchmarks?
On the tracked benchmarks, Claude Fable 5.1 leads on Terminal-Bench, and Claude Fable 5.1 leads on intelligence.
Listed prices from LiteLLM, OpenRouter and Vercel · last checked Oct 14, 2026
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