Claude Fable 5 vs GLM-5.1
Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.
Anthropic · Jun 2026
The first GA model of Anthropic's Mythos class — a tier above Opus — and the current SWE-bench Verified leader, at $10/$50 per 1M tokens.
Z.ai (Zhipu) · Apr 2026
The April 2026 GLM refresh — the first open-weights model to take #1 on SWE-bench Pro, edging out Claude Opus 4.6.
The verdict
These two models don't yet share verified results on the benchmarks we track, so judge them on specs, pricing and intended use. On price the gap is dramatic: GLM-5.1 works out roughly 9.3x cheaper per blended million tokens. Claude Fable 5 also takes 1M of context versus 200K for GLM-5.1. And GLM-5.1 is open-weights (MIT), so it can be self-hosted — a structural advantage if data control or vendor independence matters.
Specs & pricing
| Claude Fable 5 | GLM-5.1 | |
|---|---|---|
| modhub Index | — | — |
| Input price / 1M | $10 | $1.4 |
| Output price / 1M | $50 | $4.4 |
| Context window | 1M | 200K |
| Max output | 128K | 128K |
| Open weights | no | yes (MIT) |
| Reasoning model | yes | yes |
| Multimodal input | text, image | text |
| Knowledge cutoff | Jan 2026 | Feb 2026 |
| Released | Jun 2026 | Apr 2026 |
| Example monthly cost* | $175.00 | $20.60 |
* 10M input + 1.5M output tokens per month at list prices, no caching. Green = better value on that row.
Frequently asked questions
- Which is better, Claude Fable 5 or GLM-5.1?
- These two models don't yet share verified results on the benchmarks we track, so judge them on specs, pricing and intended use. On price the gap is dramatic: GLM-5.1 works out roughly 9.3x cheaper per blended million tokens. Claude Fable 5 also takes 1M of context versus 200K for GLM-5.1. And GLM-5.1 is open-weights (MIT), so it can be self-hosted — a structural advantage if data control or vendor independence matters.
- Which is cheaper, Claude Fable 5 or GLM-5.1?
- Claude Fable 5 costs $10/$50 per million input/output tokens, while GLM-5.1 costs $1.4/$4.4. For a typical workload of 10M input and 1.5M output tokens per month, that's $175.00 versus $20.60.
- Which model is better for coding, Claude Fable 5 or GLM-5.1?
- We don't yet track SWE-bench Verified results for both models; check their individual pages for coding-related scores.