Model comparison - Similar price, same tier
Gemini 3.8 Flash vs GPT-5.4 Mini
Gemini 3.8 Flash is from Google and GPT-5.4 Mini is from OpenAI. On list price, both charge $0.75 per 1M input tokens, and Gemini 3.8 Flash charges 17% less than GPT-5.4 Mini for output ($3.75 vs $4.50 per 1M tokens). Gemini 3.8 Flash has a 1,048,576-token context window and GPT-5.4 Mini 400,000 tokens; max output is 65,536 and 128,000 tokens per response. Gemini 3.8 Flash was released on September 2, 2026 and GPT-5.4 Mini on March 17, 2026. Both are closed-weights models, available only through an API.
Last verified from each provider's pricing page. All sources
Side-by-side specs
| Spec | Gemini 3.8 Flash | GPT-5.4 Mini |
|---|---|---|
| Provider | OpenAI | |
| Input / 1M tokens | $0.75 | $0.75 |
| Output / 1M tokens | $3.75 | $4.50 |
| Cache read / 1M | $0.075 | $0.075 |
| Batch input / 1M | $0.375 | $0.375 |
| Batch output / 1M | $1.875 | $2.25 |
| Context window | 1,048,576 | 400,000 |
| Max output | 65,536 | 128,000 |
| Release date | ||
| Weights | Closed | Closed |
| API model id | gemini-3.8-flash | gpt-5.4-mini |
| AI Gateway id | google/gemini-3.8-flash | openai/gpt-5.4-mini |
| Last verified |
Prices in USD per 1M tokens at each provider's standard first-party rate. A dash means the provider does not bill that item separately or no primary page states it.
What each costs in practice
The same three workloads every model page uses, worked from each model's standard list rates. Swap in your own token counts with the math on each model's page.
| Workload | Gemini 3.8 Flash | GPT-5.4 Mini |
|---|---|---|
| One agent session1M input tokens and 100K output tokens, no caching. | $1.13 | $1.20 |
| A chat app10,000 requests a day at 2K input and 500 output tokens each. | $33.75$1,012.50 per 30-day month | $37.50$1,125.00 per 30-day month |
| The same session at a 90% cache hit90% of the input is read from the prompt cache. The one-time cache write premium is not included. | $0.5175 | $0.5925 |
Show the math
Gemini 3.8 Flash
- One agent sessionInput: 1M x $0.75 = $0.75Output: 0.1M x $3.75 = $0.375
- A chat appInput: 20M x $0.75 = $15.00Output: 5M x $3.75 = $18.75
- The same session at a 90% cache hitCached input: 0.9M x $0.075 = $0.0675Uncached input: 0.1M x $0.75 = $0.075Output: 0.1M x $3.75 = $0.375
GPT-5.4 Mini
- One agent sessionInput: 1M x $0.75 = $0.75Output: 0.1M x $4.50 = $0.45
- A chat appInput: 20M x $0.75 = $15.00Output: 5M x $4.50 = $22.50
- The same session at a 90% cache hitCached input: 0.9M x $0.075 = $0.0675Uncached input: 0.1M x $0.75 = $0.075Output: 0.1M x $4.50 = $0.45
Benchmarks under the same setting
No board in the benchmark directory lists both Gemini 3.8 Flash and GPT-5.4 Mini under the same setting, so there is no like-for-like score to show here.
Set them up in your tools
Step-by-step guides whose official docs list Gemini 3.8 Flash or GPT-5.4 Mini by model id.
Model pages
FAQ
How do Gemini 3.8 Flash and GPT-5.4 Mini compare on price?
On list price, both charge $0.75 per 1M input tokens, and Gemini 3.8 Flash charges 17% less than GPT-5.4 Mini for output ($3.75 vs $4.50 per 1M tokens). For one agent session of 1M input and 100K output tokens with no caching, that is $1.13 on Gemini 3.8 Flash and $1.20 on GPT-5.4 Mini. Prices are each provider's first-party list rates, verified October 17, 2026 and October 17, 2026.
What are the context windows of Gemini 3.8 Flash and GPT-5.4 Mini?
Gemini 3.8 Flash has a 1,048,576-token context window and GPT-5.4 Mini 400,000 tokens; max output is 65,536 and 128,000 tokens per response.
Are Gemini 3.8 Flash and GPT-5.4 Mini open weights?
Gemini 3.8 Flash is closed-weights and is called through Google's API as gemini-3.8-flash. GPT-5.4 Mini is closed-weights and is called through OpenAI's API as gpt-5.4-mini.
More comparisons
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- Gemini 3.6 Flash vs Gemini 3.8 FlashSame provider, successor
- GLM-5.3 vs GPT-5.4 MiniSimilar price, same tier
- Gemini 3.8 Flash vs Grok Build 0.1Similar price, same tier
- GPT-5.4 Mini vs Grok Build 0.1Similar price, same tier
- Gemini 3.8 Flash vs Mistral Medium 3.5Similar price, same tier
Sources
Gemini 3.8 Flash verified from ai.google.dev; GPT-5.4 Mini verified from developers.openai.com. This page is as current as the older of the two: .
- https://ai.google.dev/gemini-api/docs/pricing
- https://developers.openai.com/api/docs/pricing
- https://ai.google.dev/gemini-api/docs/models/gemini-3.8-flash
- https://ai.google.dev/gemini-api/docs/changelog
- https://ai.google.dev/gemini-api/docs/models
- https://developers.openai.com/api/docs/models/gpt-5.4-mini
- https://developers.openai.com/api/docs/changelog
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