AI Agent Cost & Tools HubGemini 3.8 Flash vs GPT-5 Mini: cost comparison
Prices last verified: · how we check · price changes
Verdict
GPT-5 Mini is cheaper for both agent examples: 54% less for the customer support bot ($27.75 a month saved) and 59% less for the coding agent ($185 a month saved). If both models do your task well enough, GPT-5 Mini is the budget pick; if the other one gives clearly better answers, the extra cost may be worth it.
Prices per 1M tokens
| Gemini 3.8 Flash |   GPT-5 Mini | |
|---|---|---|
| Input / 1M | $0.75 | $0.25 |
| Output / 1M | $3.75 | $2 |
| Cached input / 1M | $0.0825 | $0.025 |
| Context | 1,048,576 | 400,000 |
Same agent workload, side by side
| Agent workload (per month) | Gemini 3.8 Flash | GPT-5 Mini | Cheaper |
|---|---|---|---|
| Customer support bot (1,000 chats/day) calculator | $51.75 | $24.00 | GPT-5 Mini (54% less) |
| Coding agent (50 tasks/day, 15 steps, 50% cached) calculator | $314 | $129 | GPT-5 Mini (59% less) |
Monthly cost by workload (no caching)
| Workload | Gemini 3.8 Flash | GPT-5 Mini | Cheaper |
|---|---|---|---|
| Chatbot (1k chats/day) | $51.75 | $24.00 | GPT-5 Mini (54% less) |
| RAG Q&A (500 queries/day) | $67.50 | $27.00 | GPT-5 Mini (60% less) |
| Coding agent (50 tasks/day, 15 steps) | $464.06 | $180.00 | GPT-5 Mini (61% less) |
| Research agent (100 tasks/day, 10 steps) | $292.50 | $120.00 | GPT-5 Mini (59% less) |
FAQ
Is Gemini 3.8 Flash cheaper than GPT-5 Mini?
GPT-5 Mini is cheaper for both agent examples: 54% less for the customer support bot ($27.75 a month saved) and 59% less for the coding agent ($185 a month saved). If both models do your task well enough, GPT-5 Mini is the budget pick; if the other one gives clearly better answers, the extra cost may be worth it.
What do Gemini 3.8 Flash and GPT-5 Mini cost per million tokens?
Gemini 3.8 Flash: $0.75 input / $3.75 output per 1M tokens. GPT-5 Mini: $0.25 input / $2 output. Prices last verified 1 Nov 2026.
Which one should a beginner pick?
Start with the cheaper model for your workload, test it on 20–50 real tasks, and only move to the pricier one if the answers are clearly not good enough. You can switch later.
Model pages
Gemini 3.8 Flash agent cost · GPT-5 Mini agent cost · All comparisons · Price changes
Generated from our daily price data; AI helped write the text. Price is not quality: test both on your own tasks. Step-by-step help: the AI Agent Cost Playbook, $29 + tax.