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GLM-5.3vsGPT-5.5 Pro

GPT-5.5 Pro leads 2 of 2 shared benchmarks. GLM-5.3 is 36.2x cheaper per token. GPT-5.5 Pro has the larger context window (1.1M tokens).

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

Shared benchmarks
0 – 2
GPT-5.5 Pro leads
Cheaper per token
GLM-5.3
36.2x cheaper, input + output
Larger context
GPT-5.5 Pro
1.1M tokens
Provider uptime (30d)
— · 94.2446%
Z.ai · OpenAI
GLM-5.3
Z.ai · released 2026-08-14
text
Context
1M
Max out
131K
Input /1M
$1.4
Output /1M
$4.4
Cached /1M
$0.26
Scores
33 · 6 core
GPT-5.5 Pro
OpenAI · released 2026-04-23
textvision
Context
1.1M
Max out
128K
Input /1M
$30
Output /1M
$180
Cached /1M
Scores
8 · 6 core
Quality

Benchmark matrix

BenchmarkGLM-5.3GPT-5.5 ProΔEdge
Reported by both · 2
FrontierMath Tier 4 v2 (Epoch AI run)29.3% epoch78% epoch-48.7 ptGPT-5.5 Pro
FrontierMath Tiers 1-3 v2 (Epoch AI run)68.8% epoch87.7% epoch-18.9 ptGPT-5.5 Pro
Only GLM-5.3 reports · 22
GPQA Diamond90.9% epochnot reported
Agents' Last Exam28.5% not reported
Agents' Last Exam (ALE-CLI)28.5% not reported
AutomationBench v1.0.648.2% not reported
CyberGym84.5% not reported
DeepSWE v1.166.9% not reported
ExploitBench54.4% not reported
ExploitGym 2h105 not reported
ExploitGym 6h130 not reported
FrontierSWE78.1% not reported
GDPval-AA v21769 not reported
HLE (with tools)62.5% not reported
NL2Repo58% not reported
OTIS Mock AIME 2024-2025 (Epoch AI run)91.1% epochnot reported
PostTrainBench39.8% not reported
ProgramBench (Almost Solved)19% not reported
SimpleQA Verified41% epochnot reported
SWE-Marathon v1.142.5% not reported
Terminal-Bench 2.188.2% not reported
Terminal-Bench 3.028.3% not reported
Toolathlon Verified73% not reported
Z.ai Code Bench (max effort)34.5% not reported
Only GPT-5.5 Pro reports · 6
Humanity's Last Exam (no tools)not reported43.1%
BrowseCompnot reported90.1%
FrontierMath Tier 1-3not reported52.4%
FrontierMath Tier 4not reported39.6%
GDPval (wins or ties)not reported82.3%
Humanity's Last Exam (with tools)not reported57.2%
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 GLM-5.3 minus GPT-5.5 Pro 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

SpecGLM-5.3GPT-5.5 ProEdge
Context window1M tokens1.1M tokensGPT-5.5 Pro
Max output131K tokens128K tokensGLM-5.3
Input price / 1M$1.4 $30 GLM-5.3
Output price / 1M$4.4 $180 GLM-5.3
Cached input / 1M$0.26
Input + output / 1M
Lower is cheaper. List prices; batch, tool and regional fees excluded.
$5.8$210GLM-5.3
Modalitiestexttext · visionGPT-5.5 Pro
Released2026-08-142026-04-23
Cited benchmark scores338
Reliability

Provider status

All providers
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