Compare · ModelsLive · 2 picked · head to head
Step 3.5 Flash vs GPT-5 Chat
Side by side · benchmarks, pricing, and signals you can act on.
Winner summary
GPT-5 Chat wins on 1/1 benchmarks
GPT-5 Chat wins 1 of 1 shared benchmarks. Leads in arena.
Category leads
arena·GPT-5 Chat
Hype vs Reality
Attention vs performance
Step 3.5 Flash
#9 by perf·#11 by attention
GPT-5 Chat
#3 by perf·#1 by attention
Best value
Step 3.5 Flash
26.4x better value than GPT-5 Chat
Step 3.5 Flash
384.5 pts/$
$0.20/M
GPT-5 Chat
14.6 pts/$
$5.63/M
Vendor risk
Mixed exposure
One or more vendors flagged
StepFun
$5.0B·Tier 1
OpenAI
$840.0B·Tier 1
Head to head
1 benchmark · 2 models
Step 3.5 FlashGPT-5 Chat
Chatbot Arena Elo · Overall
GPT-5 Chat leads by +34.7
Step 3.5 Flash
1391.4
GPT-5 Chat
1426.0
Full benchmark table
| Benchmark | Step 3.5 Flash | GPT-5 Chat |
|---|---|---|
Chatbot Arena Elo · Overall | 1391.4 | 1426.0 |
Pricing · per 1M tokens · projected $/mo at 10M tokens
| Model | Input | Output | Context | Projected $/mo |
|---|---|---|---|---|
| $0.10 | $0.30 | 262K tokens (~131 books) | $1.50 | |
| $1.25 | $10.00 | 128K tokens (~64 books) | $34.38 |