AI model comparison
Gemini 2.5 Flash vs o4 Mini
Pricing, context window, benchmarks, and features compared side by side. Or skip the guesswork and send one prompt to both.
Gemini 2.5 Flash
Gemini 2.5 Flash is Google's state-of-the-art workhorse model, specifically designed for advanced reasoning, coding, mathematics, and scientific tasks.
Gemini 2.5 Flash is scheduled to be retired on October 20, 2026. Consider Gemini 3.8 Flash instead.
- Input / 1M
- $0.30
- Output / 1M
- $2.50
- Context
- 1.05M
OpenAI
o4 Mini
OpenAI o4-mini is a compact reasoning model in the o-series, optimized for fast, cost-efficient performance while retaining strong multimodal and agentic capabilities.
- Input / 1M
- $1.10
- Output / 1M
- $4.40
- Context
- 200K
At a glance
Quick verdict
How the two models stack up on the things people ask about most.
Lower price
Gemini 2.5 Flash
2.4x cheaper for a typical chat
Higher intelligence score
o4 Mini
16.7 vs 15.5 on Artificial Analysis
Larger context window
Gemini 2.5 Flash
1.05M vs 200K tokens
Newer release
Gemini 2.5 Flash
Released June 17, 2025
Benchmarks
Benchmark scores
Independent scores from Artificial Analysis. Higher is better.
Intelligence index
Gemini 2.5 Flash15.5o4 Mini16.7Coding index
Gemini 2.5 FlashNot availableo4 MiniNot availableAgentic index
Gemini 2.5 FlashNot availableo4 MiniNot availablePricing
Gemini 2.5 Flash vs o4 Mini API pricing
Per-token API rates. Cheaper option highlighted.
| Metric | Gemini 2.5 Flash | o4 Mini |
|---|---|---|
| Input tokensPer 1M tokens | $0.30 | $1.10 |
| Output tokensPer 1M tokens | $2.50 | $4.40 |
| Cached input (read)Per 1M tokens | $0.03 | $0.28 |
| Cache writePer 1M tokens | $0.08 | Not available |
| Web searchPer request | $0.014 | $0.01 |
What it costs in practice
Estimated cost per 1,000 requests at standard rates. Coding and long-document figures also show the cost when the input is already cached.
Chat message
2K in, 500 out
Gemini 2.5 Flash$1.85o4 Mini$4.40Coding task
30K in, 4K out
Gemini 2.5 Flash$19$10.90 cachedo4 Mini$50.60$25.85 cachedLong document summary
150K in, 2K out
Gemini 2.5 Flash$50$9.50 cachedo4 Mini$173.80$50.05 cachedSpecs
Context window and capabilities
How much each model can read, how much it can write, and what it accepts as input.
| Metric | Gemini 2.5 Flash | o4 Mini |
|---|---|---|
| Context window | 1.05M tokens | 200K tokens |
| Max output | 66K tokens | 100K tokens |
| Input types | Audio, File, Image, Text, Video | File, Image, Text |
| Output types | Text | Text |
| Reasoning effort levels | Not available | Not available |
| Default reasoning effort | Not available | Not available |
| Release date | June 17, 2025 | April 16, 2025 |
Features
Supported features
API features available for each model.
| Metric | Gemini 2.5 Flash | o4 Mini |
|---|---|---|
| Tool calling | Supported | Supported |
| Structured outputs | Supported | Supported |
| JSON mode | Supported | Supported |
| Reasoning | Supported | Supported |
| Temperature | Supported | Not supported |
| Stop sequences | Supported | Not supported |
| Deterministic seed | Supported | Supported |
| Verbosity control | Not supported | Not supported |
Keep exploring
More on these models
Other head-to-heads, the full model page, and the alternatives list for each model.
Gemini 2.5 FlashView full model details- Gemini 2.5 Flash vs Step 5 Preview
- Gemini 2.5 Flash vs Gemini 3.1 Flash Lite
- Gemini 2.5 Flash vs Gemma 4 31B
- Gemini 2.5 Flash vs Gemma 4 26B A4B
- Gemini 2.5 Flash vs Claude Haiku 4.5
- Gemini 2.5 Flash vs Gemini 3.5 Flash Lite
- Gemini 2.5 Flash vs Gemini 2.5 Pro
- Gemini 2.5 Flash vs Muse Glimmer 30B
- Gemini 2.5 Flash vs GLM 4.6
- Gemini 2.5 Flash vs R1 0528
- Gemini 2.5 Flash vs Qwen3.5-122B-A10B
- Gemini 2.5 Flash vs Kimi K2 0905
- Gemini 2.5 Flash vs Mistral Medium 3.5
- Gemini 2.5 Flash vs DeepSeek V3.1 Terminus
- Gemini 2.5 Flash vs Nova 2 Lite
- Gemini 2.5 Flash vs Command A
- Gemini 2.5 Flash vs GLM 4.5
- Gemini 2.5 Flash vs Kimi K2 0711
- Gemini 2.5 Flash vs Qwen3 235B A22B Thinking 2507
- Gemini 2.5 Flash vs o3 Mini
- Gemini 2.5 Flash vs MiniMax M1
- Gemini 2.5 Flash vs R1
Our take
Gemini 2.5 Flash is 2.4x cheaper for a typical chat. o4 Mini scores higher on the Artificial Analysis Intelligence Index (16.7 vs 15.5). Gemini 2.5 Flash has the larger context window (1.05M vs 200K tokens). The right pick depends on your workload, so the quickest way to settle it is to send the same prompt to both and compare.
FAQ
Frequently asked questions
Is Gemini 2.5 Flash or o4 Mini cheaper?
Gemini 2.5 Flash is cheaper for a typical chat (2K input tokens and 500 output tokens). Gemini 2.5 Flash costs $0.30 per 1M input tokens and $2.50 per 1M output tokens, while o4 Mini costs $1.10 per 1M input tokens and $4.40 per 1M output tokens.
Which has a bigger context window, Gemini 2.5 Flash or o4 Mini?
Gemini 2.5 Flash supports up to 1.05M tokens of context, compared with 200K for o4 Mini.
Is Gemini 2.5 Flash smarter than o4 Mini?
On the Artificial Analysis Intelligence Index, Gemini 2.5 Flash scores 15.5 and o4 Mini scores 16.7, putting o4 Mini ahead. Benchmarks don't capture everything, so the best test is running your own prompts through both.
Can I use Gemini 2.5 Flash and o4 Mini at the same time?
Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see Gemini 2.5 Flash and o4 Mini answer side by side and keep the better response.
Why choose? Ask both.
Send one prompt to Gemini 2.5 Flash and o4 Mini at the same time. Compare the answers side by side and keep the best one.