Compare · ModelsLive · 2 picked · head to head

GLM 5.1 vs Step 3.5 Flash

Side by side · benchmarks, pricing, and signals you can act on.

Winner summary

GLM 5.1 wins 4 of 4 shared benchmarks. Leads in speed · arena.

Category leads
speed·GLM 5.1arena·GLM 5.1
Hype vs Reality
GLM 5.1
#16 by perf·no signal
QUIET
Step 3.5 Flash
#9 by perf·#11 by attention
DESERVED
Best value
12.5x better value than GLM 5.1
GLM 5.1
30.9 pts/$
$2.27/M
Step 3.5 Flash
384.5 pts/$
$0.20/M
Vendor risk
One or more vendors flagged
z-ai logo
z-ai
private · undisclosed
Unknown
stepfun logo
StepFun
$5.0B·Tier 1
Higher risk
Head to head
GLM 5.1Step 3.5 Flash
Artificial Analysis · Agentic Index
GLM 5.1 leads by +15.0
Artificial Analysis Agentic Index · a composite score measuring how well a model performs in agentic workflows · multi-step tool use, planning, error recovery, and autonomous task completion. Aggregates results from multiple agentic benchmarks including SWE-bench, tool-use tests, and planning evaluations. The canonical single-number metric for "how good is this model as an agent?"
GLM 5.1
67.0
Step 3.5 Flash
52.0
Artificial Analysis · Coding Index
GLM 5.1 leads by +11.7
Artificial Analysis Coding Index · a composite score that aggregates performance across multiple coding benchmarks into a single index. Tracks code generation quality, debugging ability, multi-language competence, and real-world software engineering tasks. Used by Artificial Analysis to rank model coding capability in a normalized, comparable format. Useful for developers choosing between models for coding-heavy workloads.
GLM 5.1
43.4
Step 3.5 Flash
31.6
Artificial Analysis · Quality Index
GLM 5.1 leads by +13.6
GLM 5.1
51.4
Step 3.5 Flash
37.8
Chatbot Arena Elo · Overall
GLM 5.1 leads by +76.0
GLM 5.1
1467.4
Step 3.5 Flash
1391.4
Full benchmark table
BenchmarkGLM 5.1Step 3.5 Flash
Artificial Analysis · Agentic Index
Artificial Analysis Agentic Index · a composite score measuring how well a model performs in agentic workflows · multi-step tool use, planning, error recovery, and autonomous task completion. Aggregates results from multiple agentic benchmarks including SWE-bench, tool-use tests, and planning evaluations. The canonical single-number metric for "how good is this model as an agent?"
67.052.0
Artificial Analysis · Coding Index
Artificial Analysis Coding Index · a composite score that aggregates performance across multiple coding benchmarks into a single index. Tracks code generation quality, debugging ability, multi-language competence, and real-world software engineering tasks. Used by Artificial Analysis to rank model coding capability in a normalized, comparable format. Useful for developers choosing between models for coding-heavy workloads.
43.431.6
Artificial Analysis · Quality Index
51.437.8
Chatbot Arena Elo · Overall
1467.41391.4
Pricing · per 1M tokens · projected $/mo at 10M tokens
ModelInputOutputContextProjected $/mo
z-ai logoGLM 5.1$1.05$3.50203K tokens (~101 books)$16.63
stepfun logoStep 3.5 Flash$0.10$0.30262K tokens (~131 books)$1.50