AI model comparison
GLM 5.3 vs Claude Opus 4.8
Pricing, context window, benchmarks, and features compared side by side. Or skip the guesswork and send one prompt to both.
Z.ai
GLM 5.3
GLM-5.3 is a large-scale reasoning model from Z.ai, built for complex software engineering and long-horizon agent tasks.
- Input / 1M
- $0.04
- Output / 1M
- $7
- Context
- 1.05M
Anthropic
Claude Opus 4.8
Claude Opus 4.8 is Anthropic's most capable generally available model in the Opus family.
- Input / 1M
- $5
- Output / 1M
- $25
- Context
- 1M
At a glance
Quick verdict
How the two models stack up on the things people ask about most.
Lower price
GLM 5.3
6.3x cheaper for a typical chat
Higher intelligence score
GLM 5.3
44.8 vs 41.8 on Artificial Analysis
Larger context window
GLM 5.3
1.05M vs 1M tokens
Newer release
GLM 5.3
Released August 18, 2026
Benchmarks
Benchmark scores
Independent scores from Artificial Analysis. Higher is better.
Intelligence index
Claude Opus 4.841.8Coding index
Claude Opus 4.874.3Agentic index
Claude Opus 4.841.9Pricing
GLM 5.3 vs Claude Opus 4.8 API pricing
Per-token API rates. Cheaper option highlighted.
| Metric | Claude Opus 4.8 | |
|---|---|---|
| Input tokensPer 1M tokens | $0.04 | $5 |
| Output tokensPer 1M tokens | $7 | $25 |
| Cached input (read)Per 1M tokens | $0.04 | $0.50 |
| Cache writePer 1M tokens | Not available | $6.25 |
| Web searchPer request | Not available | $0.01 |
What it costs in practice
Estimated cost per 1,000 requests at standard rates. Coding and long-document figures also show the cost when the input is already cached.
Chat message
2K in, 500 out
Claude Opus 4.8$22.50Coding task
30K in, 4K out
Claude Opus 4.8$250$115 cachedLong document summary
150K in, 2K out
Claude Opus 4.8$800$125 cachedSpecs
Context window and capabilities
How much each model can read, how much it can write, and what it accepts as input.
| Metric | Claude Opus 4.8 | |
|---|---|---|
| Context window | 1.05M tokens | 1M tokens |
| Max output | 944K tokens | 128K tokens |
| Input types | Text | File, Image, Text |
| Output types | Text | Text |
| Reasoning effort levels | Max, High, Low | Max, Extra high, High, Medium, Low |
| Default reasoning effort | Max | High |
| Release date | August 18, 2026 | May 27, 2026 |
Features
Supported features
API features available for each model.
| Metric | Claude Opus 4.8 | |
|---|---|---|
| Tool calling | Supported | Supported |
| Structured outputs | Supported | Supported |
| JSON mode | Supported | Supported |
| Reasoning | Supported | Supported |
| Temperature | Supported | Not supported |
| Stop sequences | Supported | Supported |
| Deterministic seed | Supported | Not supported |
| Verbosity control | Not supported | Supported |
Keep exploring
More on these models
Other head-to-heads, the full model page, and the alternatives list for each model.
- GLM 5.3 vs DeepSeek V4.1 Flash
- GLM 5.3 vs GLM 5.3 Flash
- GLM 5.3 vs MiMo-V2.6-Flash
- GLM 5.3 vs Hy4 preview
- GLM 5.3 vs GPT-6 Luna
- GLM 5.3 vs Claude Opus 5.5
- GLM 5.3 vs DeepSeek V4 Flash 0731
- GLM 5.3 vs Claude Sonnet 5.5
- GLM 5.3 vs GPT-6 Astra
- GLM 5.3 vs DeepSeek V4 Flash 0423
- GLM 5.3 vs GPT-6.1 Sol
- GLM 5.3 vs Step 5 Preview
- GLM 5.3 vs Gemini 3.8 Flash
- GLM 5.3 vs Hy3
- GLM 5.3 vs Muse Spark 1.3
- GLM 5.3 vs GPT-6 Sol
- GLM 5.3 vs Kimi K3
- GLM 5.3 vs GPT-5.6 Sol
- GLM 5.3 vs Grok 4.7
- GLM 5.3 vs MiMo-V2.6-Pro
- GLM 5.3 vs Qwen3.8 Max (0902)
- GLM 5.3 vs GLM 5.2
- GLM 5.3 vs Grok 4.6
- GLM 5.3 vs Claude Haiku 5.5
- GLM 5.3 vs GPT-5.6 Terra
- GLM 5.3 vs Ling 3.1 Flash
- GLM 5.3 vs Claude Opus 4.7
- GLM 5.3 vs Qwen3.8 2.4T A95B
- GLM 5.3 vs Gemini 3.7 Flash
- GLM 5.3 vs Muse Spark 1.2
- GLM 5.3 vs Grok 4.5
Claude Opus 4.8View full model details- Claude Opus 4.8 vs Claude Fable 5.1
- Claude Opus 4.8 vs Claude Opus 5
- Claude Opus 4.8 vs Claude Fable 5
- Claude Opus 4.8 vs Kimi K3
- Claude Opus 4.8 vs GPT-5.6 Terra
- Claude Opus 4.8 vs Ling 3.1 Flash
- Claude Opus 4.8 vs Gemini 3.8 Flash
- Claude Opus 4.8 vs Claude Opus 4.7
- Claude Opus 4.8 vs DeepSeek V4.1 Flash
- Claude Opus 4.8 vs GPT-5.4
- Claude Opus 4.8 vs GPT-5.5
- Claude Opus 4.8 vs Claude Sonnet 5
- Claude Opus 4.8 vs Claude Opus 4.6
Our take
GLM 5.3 is 6.3x cheaper for a typical chat. GLM 5.3 scores higher on the Artificial Analysis Intelligence Index (44.8 vs 41.8). GLM 5.3 has the larger context window (1.05M vs 1M tokens). The right pick depends on your workload, so the quickest way to settle it is to send the same prompt to both and compare.
FAQ
Frequently asked questions
Is GLM 5.3 or Claude Opus 4.8 cheaper?
GLM 5.3 is cheaper for a typical chat (2K input tokens and 500 output tokens). GLM 5.3 costs $0.04 per 1M input tokens and $7 per 1M output tokens, while Claude Opus 4.8 costs $5 per 1M input tokens and $25 per 1M output tokens.
Which has a bigger context window, GLM 5.3 or Claude Opus 4.8?
GLM 5.3 supports up to 1.05M tokens of context, compared with 1M for Claude Opus 4.8.
Is GLM 5.3 smarter than Claude Opus 4.8?
On the Artificial Analysis Intelligence Index, GLM 5.3 scores 44.8 and Claude Opus 4.8 scores 41.8, putting GLM 5.3 ahead. Benchmarks don't capture everything, so the best test is running your own prompts through both.
Can I use GLM 5.3 and Claude Opus 4.8 at the same time?
Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see GLM 5.3 and Claude Opus 4.8 answer side by side and keep the better response.
Why choose? Ask both.
Send one prompt to GLM 5.3 and Claude Opus 4.8 at the same time. Compare the answers side by side and keep the best one.