Claude Opus 4.6 vs GLM 5
Claude Opus 4.6 (Anthropic, released 2026-02-04) and GLM 5 (Z.ai, released 2026-02-11) are both built for long-horizon coding agents, but they land in different tiers. Opus 4.6 has a 1M token context window and premium pricing; GLM 5 has roughly a fifth of that context at a fraction of the price. Across every shared Design Arena category, Opus 4.6 ranks higher. The question isn't which is better in the abstract — it's whether your workload can absorb an 8.33x input price gap for the quality difference.
Spec vs spec
| Spec | Claude Opus 4.6 | GLM 5 |
|---|---|---|
| Context window | 1M | 203K |
| Max output | 128K | — |
| Input modalities | text, image, file | text |
| Output modalities | text | text |
| Released | Feb 4, 2026 | Feb 11, 2026 |
| Reasoning | optional | optional |
Pricing
Per 1M tokens. Provider price plus the flat 3% fee — the sum is what you pay.
anthropic/claude-opus-4.6
Input · 1M tokens
$5.00 + 3%$5.15
Output · 1M tokens
$25.00 + 3%$25.75
Cache read · 1M tokens
$0.500 + 3%$0.515
Cache write · 1M tokens
$6.25 + 3%$6.44
FEE — FLAT, EVERY MODEL3%
z-ai/glm-5
Input · 1M tokens
$0.600 + 3%$0.618
Output · 1M tokens
$1.92 + 3%$1.98
Cache read · 1M tokens
$0.120 + 3%$0.124
FEE — FLAT, EVERY MODEL3%
One workload, priced on both
10M input + 2M output tokens at each model's price, flat 3% fee included.
anthropic/claude-opus-4.6
$103.00
$100.00 provider + 3%
z-ai/glm-5Cheaper
$10.14
$9.84 provider + 3%
Benchmarks
Design Arena categories where both models have results. Higher Elo and lower rank win.
| Claude Opus 4.6 | GLM 5 | |||
|---|---|---|---|---|
| Category | Elo | Rank | Elo | Rank |
| 3D | 1351 | #4 | 1307 | #15 |
| androidnative | 1216 | #11 | 1244 | #6 |
| ASCII art | 1307 | #6 | 1192 | #26 |
| Code | 1342 | #3 | 1295 | #16 |
| Data viz | 1322 | #5 | 1269 | #22 |
| Full-stack | 1288 | #4 | 1190 | #13 |
| Game dev | 1344 | #4 | 1299 | #15 |
| Mobile apps | 1261 | #3 | 1222 | #10 |
| SVG | 1288 | #4 | 1225 | #19 |
| UI components | 1350 | #3 | 1287 | #21 |
| Websites | 1338 | #3 | 1290 | #18 |
Head-to-head preference voting. How we filter and rank
Pricing math on a real workload
Provider list price for Opus 4.6 is $5.00/$25.00 per million input/output tokens; on OpenKey that's $5.00 x 1.03 = $5.15 in and $25.00 x 1.03 = $25.75 out. GLM 5 lists at $0.60/$1.92; on OpenKey that's $0.60 x 1.03 = $0.618 in and $1.92 x 1.03 = $1.9776 out — both flat 3% on top of provider price, no markup games.
Run the numbers on a 10M-input / 2M-output workload and the gap is stark: Opus 4.6 costs $100.00, GLM 5 costs $9.84. That's the input_price_ratio of 8.33x showing up directly in your bill. If you're processing high volumes of tokens — batch jobs, high-frequency agent loops — this is the number that decides your model, not the benchmark chart.
Coding and agent benchmarks
Design Arena data covers both models across agent and model-quality categories. Opus 4.6 ranks 3rd-11th across agent categories (fullstack rank 4, mobileapps rank 3, webapps rank 4, androidnative rank 11) with win rates from 60.5% to 68.8%. GLM 5 ranks 3rd-13th on the same arena but with notably lower win rates on the categories they share — fullstack at 52.8% (rank 13) versus Opus 4.6's 68.6% (rank 4).
On model-quality categories the gap widens further: GLM 5 drops to rank 15-26 on 3d, asciiart, dataviz, svg, uicomponent, and website, where Opus 4.6 holds rank 3-6 across the board. If code quality on complex tasks is the bottleneck, Opus 4.6 is the clear pick.
Context and long documents
Opus 4.6 gives you 1,000,000 tokens of context against GLM 5's 202,752 — a context_ratio of 4.93x. For codebases, long agent transcripts, or multi-document analysis that need to stay in one context window, Opus 4.6 has meaningfully more room. GLM 5's window is still large enough for most single-repo or single-document tasks, but if you're feeding in an entire monorepo or a long chat history, Opus 4.6's window buys you more headroom before you have to chunk or summarize.
Modality and output limits
Opus 4.6 accepts text, image, and file input and caps completions at 128,000 tokens. GLM 5 is text-only, in and out, with no stated max completion token limit in this data. If your workflow needs to hand the model a screenshot, a PDF, or a diagram alongside code, GLM 5 is out — it simply doesn't take that input. Opus 4.6 also exposes more inference controls (verbosity, top_k, reasoning effort levels from low to max) versus GLM 5's more standard parameter set, though GLM 5 does support logprobs and seed, which Opus 4.6 doesn't list.
Which model for which job
| Use case | Pick | Why |
|---|---|---|
| Production coding agent | Claude Opus 4.6 | Ranks 3rd-4th across fullstack, mobileapps, and webapps agent categories vs GLM 5's 10th-13th |
| High-volume batch processing | GLM 5 | Costs $9.84 vs $100.00 on the 10M-in/2M-out benchmark workload |
| Whole-repo or long-document analysis | Claude Opus 4.6 | 1M token context vs 202,752 — 4.93x more room |
| Image or file-based coding tasks | Claude Opus 4.6 | Only one with image and file input modalities; GLM 5 is text-only |
| Budget-constrained prototyping | GLM 5 | Input price is 8.33x cheaper, so iteration cost stays low |
| UI component or website generation quality | Claude Opus 4.6 | Rank 3 on uicomponent and website vs GLM 5's rank 21 and 18 |
Questions
- How much cheaper is GLM 5 than Claude Opus 4.6?
- On a 10M-input / 2M-output workload, GLM 5 costs $9.84 versus $100.00 for Opus 4.6 — roughly a 10x difference in total cost, driven by an input_price_ratio of 8.33x ($5.15 vs $0.618 per million input tokens on OpenKey).
- Which model has a bigger context window?
- Claude Opus 4.6 supports 1,000,000 tokens of context versus GLM 5's 202,752 — a context_ratio of 4.93x. If you're working with large codebases or long documents, Opus 4.6 has more room before you need to chunk input.
- Does GLM 5 support image input like Opus 4.6?
- No. GLM 5 is text-to-text only. Opus 4.6 supports text, image, and file input, which matters if your agent workflow needs to read screenshots or PDFs alongside code.
- Which model wins on coding benchmarks?
- Claude Opus 4.6 ranks higher in every shared Design Arena category, including rank 4 vs rank 13 on fullstack agent tasks (68.6% vs 52.8% win rate) and rank 3 vs rank 21 on uicomponent generation. Both models are available through OpenKey with one API key and a flat 3% fee on provider list price.