Claude Opus 5 (Fast) alternatives
Match · Updated July 2026
The closest alternative to Claude Opus 5 (Fast) is Claude Opus 5 — comparable intelligence (— vs —); for a cheaper option, GPT-5.6 Sol runs $5.00/M vs $10.00/M; for more speed, Gemini 2.5 Flash Lite hits 166 t/s; and the best open-weight substitute is GLM 5.2.
Closest match
Cheaper alternatives
gpt-5.6-sol
$5.00/M input · 58.9 intel
kimi-k3
$3.00/M input · 57.1 intel
claude-opus-4.8
$5.00/M input · 55.7 intel
gpt-5.6-terra
$2.50/M input · 55.0 intel
gpt-5.5
$5.00/M input · 54.8 intel
grok-4.5
$2.00/M input · 53.8 intel
Faster alternatives
gemini-2.5-flash-lite
166 t/s · 346ms ttft
gemini-3.1-pro-preview
158 t/s · 2.9s ttft
gemini-3.6-flash
146 t/s · 2.2s ttft
gpt-5.4-mini
145 t/s · 1.1s ttft
gpt-5.6-luna
127 t/s · 1.9s ttft
gemini-3.1-flash-lite
115 t/s · 442ms ttft
Open-source alternatives
glm-5.2
51.1 intel · open weights · 1.0M ctx
minimax-m3
44.4 intel · open weights · 1.0M ctx
deepseek-v4-pro
44.3 intel · open weights · 1.0M ctx
kimi-k2.6
44.2 intel · open weights · 262K ctx
mimo-v2.5-pro
42.2 intel · open weights · 1.1M ctx
kimi-k2.7-code
41.9 intel · open weights · 262K ctx
Frequently asked
What is the best alternative to Claude Opus 5 (Fast)?
Claude Opus 5 is the closest alternative to Claude Opus 5 (Fast), with an Intelligence Index of — (Claude Opus 5 (Fast) scores —) at $5.00 per million input tokens.
Is there a cheaper alternative to Claude Opus 5 (Fast)?
Yes — GPT-5.6 Sol costs $5.00 per million input tokens versus $10.00 for Claude Opus 5 (Fast), while staying within ~8 points of its Intelligence Index.
Is there an open-source alternative to Claude Opus 5 (Fast)?
GLM 5.2 is the strongest open-weight alternative to Claude Opus 5 (Fast) — downloadable from Hugging Face and self-hostable, scoring 51.1 on intelligence.