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Claude Opus 4.8vsGLM-5.1

Claude Opus 4.8 leads 5 of 6 shared benchmarks. GLM-5.1 is 5.2x cheaper per token. Claude Opus 4.8 has the larger context window (1M tokens).

Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.

Shared benchmarks
5 – 1
Claude Opus 4.8 leads
Cheaper per token
GLM-5.1
5.2x cheaper, input + output
Larger context
Claude Opus 4.8
1M tokens
Provider uptime (30d)
100% · —
Anthropic · Z.ai
Claude Opus 4.8
Anthropic · released 2026-05-28
textvision
Context
1M
Max out
128K
Input /1M
$5
Output /1M
$25
Cached /1M
$0.5
Scores
17 · 13 core
GLM-5.1
Z.ai · released 2026-04-07
text
Context
200K
Max out
131K
Input /1M
$1.4
Output /1M
$4.4
Cached /1M
$0.26
Scores
7 · 7 core
Quality

Benchmark matrix

BenchmarkClaude Opus 4.8GLM-5.1ΔEdge
Reported by both · 6
GPQA Diamond93.6% 89.9% epoch+3.7 ptClaude Opus 4.8
AIME 2026100% matharena95.8% matharena+4.2 ptClaude Opus 4.8
LMArena Elo1452.7 1462.4 -9.7GLM-5.1
FrontierMath Tiers 1-3 v2 (Epoch AI run)80% epoch36.8% epoch+43.2 ptClaude Opus 4.8
OTIS Mock AIME 2024-2025 (Epoch AI run)98.3% epoch93.3% epoch+5 ptClaude Opus 4.8
SimpleQA Verified53% epoch34% epoch+19 ptClaude Opus 4.8
Only Claude Opus 4.8 reports · 10
SWE-bench Verified88.6% not reported
Humanity's Last Exam (no tools)49.8% not reported
BrowseComp84.3% not reported
FrontierMath Tier 4 v2 (Epoch AI run)56.1% epochnot reported
Humanity's Last Exam (with tools)57.9% not reported
OSWorld-Verified83.4% not reported
SWE-bench Multilingual84.4% not reported
SWE-bench Multimodal38.4% not reported
SWE-Bench Pro69.2% not reported
Terminal-Bench 2.174.6% not reported
Only GLM-5.1 reports · 1
SWE-bench Verified (Epoch AI run)not reported74.2% epoch
Scores tagged "epoch" or "matharena" are independent runs, used only where the lab has not published its own; ⚠ marks rows MathArena flags as released after the competition. Higher is better on every row. Δ is Claude Opus 4.8 minus GLM-5.1 in the benchmark's own unit. "Not reported" means the lab has not published that figure; it is not a zero. ↗ opens the source.
Specs & pricing

Side by side

SpecClaude Opus 4.8GLM-5.1Edge
Context window1M tokens200K tokensClaude Opus 4.8
Max output128K tokens131K tokensGLM-5.1
Input price / 1M$5 $1.4 GLM-5.1
Output price / 1M$25 $4.4 GLM-5.1
Cached input / 1M$0.5 $0.26 GLM-5.1
Input + output / 1M
Lower is cheaper. List prices; batch, tool and regional fees excluded.
$30$5.8GLM-5.1
Modalitiestext · visiontextClaude Opus 4.8
Released2026-05-282026-04-07
Cited benchmark scores177
Reliability

Provider status

All providers
More matchups

Claude Opus 4.8 vs …

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