GLM 5.1: what 67 developers actually say.
67 Hacker News opinions from 50 developers, Nov 2025 – Nov 2026. 54 come from people who say they use it. Here is what they praise, what they complain about, and who switched.
The case for GLM 5.1, in one paragraph.
GLM 5.1 earns 78% approval across 67 opinions. Developers praise its code quality.
Pick it if you
- Want strong code quality at a low price
- Are running long agent tasks on a tight budget
- Want a model that works well in OpenCode or a spec-driven workflow
Look elsewhere if you
- Need stable behavior past 200k tokens of context
- Depend on security work, which it often refuses
- Need fast responses during peak hours
Where it wins and loses.
Mentions across 67 opinions. Bars are counts, not votes; a tool can be both praised and criticized on the same topic.
View data table
| Topic | Praise | Complaints | Mentions |
|---|---|---|---|
| Code quality | 28 | 4 | 32 |
| Cost & pricing | 18 | 0 | 18 |
How opinion has moved.
Monthly approval, Apr 2026 – Jun 2026. Bars show opinion volume; low-volume months are still included but faded.
View data table
| Month | Approval | Opinions |
|---|---|---|
| Apr 2026 | 78% | 36 |
| May 2026 | 95% | 10 |
| Jun 2026 | 68% | 19 |
What developers say.
Summaries are paraphrased. Each links to the original Hacker News comment.
Praise
4 selectedWas very happy with GLM 5.1 for their spec-driven coding workflow.
GLM 5.1 fixed many low-level programming issues that Opus kept looping on.
Experimenting with GLM 5.1 gives quite good results for the price on bigger tasks.
Switched from Kimi K2.5 to GLM 5.1 and feels it is a step above.
Complaints
4 selectedAdvises against very low-bit quantizations of GLM 5.1, finding smaller models more reliable.
Reports the same disappointing experience with GLM 5.1 as with DeepSeek Pro.
GLM 5.1 performance degraded after about 200k tokens of context in their use on the coding plan.
GLM 5.1 refuses almost any security task, so they moved that work to Fable.
Questions developers ask.
Is GLM 5.1 worth it?
Is GLM 5.1 better than Claude Opus?
How does GLM 5.1 handle long context?
The data behind this page.
Developers give GLM 5.1 a 78% approval score across 67 opinions from 50 authors, and 54 of those opinions come from direct users. Code quality is the strongest theme at 28 positive mentions against 4 negative, and cost follows at 18 positive with none negative. Monthly approval fell from 95 in May to 68 in June on 19 opinions, so the recent direction is down. July holds only 1 opinion, too few to call a recovery.
Every number comes from public Hacker News comments collected through the HN Search API. A language model tagged each comment for sentiment, first-hand use, topic and switches; a human spot-checks samples. No vendor can pay for placement.
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