Google · Efficient
Gemini 2.5 Flash Preview (09/2025)
State-of-the-art Gemini 2.5 Flash checkpoint tuned for advanced reasoning, coding, math, and scientific tasks. Built-in thinking for higher accuracy and nuanced context handling. Routed to Gemini 2.5 Flash (stable).
- Reasoning
- Tools
- Vision
- Structured output
- PDF input
- Audio input
- Input
- Text, Images, Audio
- Output
- Text
- Reasoning effort
- low · medium · high
- Discovery tier
- Efficient
Pricing
USD per 1M tokens- Input
- $0.30
- Output
- $2.50
- Cache read
- $0.03
Reference prices as published by the model provider. API example
Specifications
- Context window
- 1M
- Max output
- 65.5K
Side by side
Gemini 2.5 Flash Preview (09/2025) compared
Specifications, prices, speed and benchmark scores next to each other. Benchmarks below show every compared model too.
| Gemini 2.5 Flash Preview (09/2025)GoogleThis model | Gemini 3.8 FlashGoogleRemove | |
|---|---|---|
| Provider | ||
| Discovery tier | Efficient | Efficient |
| Added | Sep 25, 2025 | Sep 2, 2026 |
| Limits | ||
| Context window | 1.05M | 1.05M |
| Max output | 65.54K | 65.54K |
| Average output | — | 1.2K tokens |
| Pricing, USD per 1M tokens | ||
| Input | $0.30Best | $0.75 |
| Output | $2.50Best | $3.75 |
| Cache read | $0.03Best | $0.075 |
| Cache write | — | $0.0417 |
| Performance | ||
| Throughput | — | 185.2 tok/s |
| Time to first token | — | 8.5 s |
| Request success (24h) | 99.7% | 99.9%Best |
| Benchmark indexes | ||
| Intelligence Index | 12.4 | 39.8Best |
| Coding Index | — | 74.1 |
| Math Index | 56.7 | — |
| Capabilities | ||
| Reasoning | Yes | Yes |
| Tools | Yes | Yes |
| Vision | Yes | Yes |
| Structured output | Yes | Yes |
| PDF input | Yes | Yes |
| Audio input | Yes | Yes |
| Video input | No | Yes |
| Reasoning effort | low, medium, high | minimal, low, medium, high |
Public evaluations
Benchmarks
Independent evaluation results, with how each score ranks among the models in the Noumen catalog.
- Gemini 2.5 Flash Preview (09/2025)
- Gemini 3.8 Flash
Intelligence Index
- Gemini 2.5 Flash Preview (09/2025)12.4
- Gemini 3.8 Flash39.8
Gemini 2.5 Flash Preview (09/2025): Better than 26% of 326 scored models
Indexes
Coding Index
Composite of the coding evaluations
- Gemini 2.5 Flash Preview (09/2025): —
- Gemini 3.8 Flash: 74.1
Math Index
Composite of the math evaluations
- Gemini 2.5 Flash Preview (09/2025): 56.7
- Gemini 3.8 Flash: —
Agentic work
AutomationBench-AA
Workflow automation, penalized for guardrail violations
- Gemini 2.5 Flash Preview (09/2025): —
- Gemini 3.8 Flash: 60.9%
AutomationBench-AA tasks completed
Workflows finished end to end without a guardrail violation
- Gemini 2.5 Flash Preview (09/2025): —
- Gemini 3.8 Flash: 31.1%
AA-Briefcasev1.1
Agentic knowledge work, rated head to head
- Gemini 2.5 Flash Preview (09/2025): —
- Gemini 3.8 Flash: 1,181 Elo
GDPval-AAv2.1
Economically valuable occupational tasks, rated head to head
- Gemini 2.5 Flash Preview (09/2025): —
- Gemini 3.8 Flash: 1,423 Elo
Document reasoning
GDP.pdf
Professional reasoning over PDF documents, all-pass rate
- Gemini 2.5 Flash Preview (09/2025): —
- Gemini 3.8 Flash: 22.8%
AA-LCRv1.1
Reasoning across long documents
- Gemini 2.5 Flash Preview (09/2025): 60.0%
- Gemini 3.8 Flash: 84.0%Top
MLCR-AA
Long-context reasoning over medical records
- Gemini 2.5 Flash Preview (09/2025): —
- Gemini 3.8 Flash: 12.8%
Reasoning and knowledge
Humanity’s Last Exam
Expert-level questions across academic fields
- Gemini 2.5 Flash Preview (09/2025): 8.7%
- Gemini 3.8 Flash: 42.1%Top
GPQA Diamond
Graduate-level science questions
- Gemini 2.5 Flash Preview (09/2025): 76.6%
- Gemini 3.8 Flash: 93.5%Top
MMLU-Pro
Multi-subject knowledge and reasoning
- Gemini 2.5 Flash Preview (09/2025): 83.6%
- Gemini 3.8 Flash: —
IFBench
Following precise output instructions
- Gemini 2.5 Flash Preview (09/2025): 43.5%
- Gemini 3.8 Flash: —
Coding
Terminal-Benchv4.0
Practical software engineering in a terminal
- Gemini 2.5 Flash Preview (09/2025): —
- Gemini 3.8 Flash: 19.7%
SciCode
Scientific computing in Python
- Gemini 2.5 Flash Preview (09/2025): —
- Gemini 3.8 Flash: 55.1%
LiveCodeBench
Recent competitive programming problems
- Gemini 2.5 Flash Preview (09/2025): 62.5%
- Gemini 3.8 Flash: —
Math
AIME 2025
Competition mathematics, 2025 problems
- Gemini 2.5 Flash Preview (09/2025): 56.7%
- Gemini 3.8 Flash: —
Legacy evaluations
Terminal-Bench Hard
Earlier terminal task suite
- Gemini 2.5 Flash Preview (09/2025): 14.4%
- Gemini 3.8 Flash: —
τ²-Bench Telecom
Tool use in a customer-support simulation
- Gemini 2.5 Flash Preview (09/2025): 28.4%
- Gemini 3.8 Flash: —
AA-LCR (unversioned)
Long-context reasoning, earlier grading
- Gemini 2.5 Flash Preview (09/2025): 60.0%
- Gemini 3.8 Flash: 84.0%Top
Scores from Artificial Analysis, updated Oct 26, 2026. Artificial Analysis
- Gemini 2.5 Flash Preview (09/2025)
- Gemini 3.8 Flash
| Leaderboard | Gemini 2.5 Flash Preview (09/2025) | Gemini 3.8 Flash |
|---|---|---|
| Vision Style Control · Creative Writing | #4 · 1263.4 | Not in top 20 |
| Overall | Not in top 20 | #8 · 1495.7 |
| Math | Not in top 20 | #3 · 1525.9 |
| Longer Query | Not in top 20 | #7 · 1509.9 |
| Creative Writing | Not in top 20 | #9 · 1485.1 |
| Instruction Following | Not in top 20 | #11 · 1490.2 |
| Hard Prompts | Not in top 20 | #8 · 1517.3 |
| Chinese | Not in top 20 | #12 · 1538.3 |
| English | Not in top 20 | #9 · 1498.0 |
| Exclude Ties | Not in top 20 | #9 · 1513.6 |
| Expert | Not in top 20 | #12 · 1527.5 |
| German | Not in top 20 | #8 · 1501.8 |
| Hard Prompts English | Not in top 20 | #11 · 1514.0 |
| Industry Entertainment And Sports And Media | Not in top 20 | #9 · 1477.4 |
| Industry Life And Physical And Social Science | Not in top 20 | #9 · 1519.3 |
| Industry Mathematical | Not in top 20 | #10 · 1513.9 |
| Industry Medicine And Healthcare | Not in top 20 | #10 · 1507.7 |
| Industry Software And It Services | Not in top 20 | #18 · 1517.5 |
| Industry Writing And Literature And Language | Not in top 20 | #9 · 1490.5 |
| Japanese | Not in top 20 | #7 · 1508.3 |
| Korean | Not in top 20 | #13 · 1459.7 |
| Multi Turn | Not in top 20 | #7 · 1504.4 |
| Non English | Not in top 20 | #8 · 1486.3 |
| Polish | Not in top 20 | #13 · 1492.9 |
| Russian | Not in top 20 | #5 · 1515.1 |
| Spanish | Not in top 20 | #18 · 1478.0 |
| Vision Style Control Overall | Not in top 20 | #8 · 1291.0 |
| Vision Style Control · Chinese | Not in top 20 | #1 · 1383.7 |
| Vision Style Control · Creative Writing Vision | Not in top 20 | #16 · 1275.7 |
| Vision Style Control · Diagram | Not in top 20 | #2 · 1333.3 |
| Vision Style Control · English | Not in top 20 | #4 · 1291.5 |
| Vision Style Control · Homework | Not in top 20 | #5 · 1338.4 |
| Vision Style Control · Humor | Not in top 20 | #3 · 1297.9 |
| Vision Style Control · Ocr | Not in top 20 | #2 · 1316.0 |
| WebDev · Image To Webdev | Not in top 20 | #15 · 1592.7 |
Ranks among Noumen catalog models on LMArena leaderboards. Only top-20 placements are listed.LMArena
- Gemini 2.5 Flash Preview (09/2025)
- Gemini 3.8 Flash
| Leaderboard | Gemini 2.5 Flash Preview (09/2025) | Gemini 3.8 Flash |
|---|---|---|
| Combined | Not in top 20 | #16 · 9.3% |
Ranks among Noumen catalog models on Combined leaderboards. Only top-20 placements are listed.
- Gemini 2.5 Flash Preview (09/2025)
- Gemini 3.8 Flash
| Leaderboard | Gemini 2.5 Flash Preview (09/2025) | Gemini 3.8 Flash |
|---|---|---|
| Creative writing | Not in top 20 | #19 · 15.2% |
| Math | Not in top 20 | #3 · 41.9% |
Ranks among Noumen catalog models on Use cases leaderboards. Only top-20 placements are listed.
- Gemini 2.5 Flash Preview (09/2025)
- Gemini 3.8 Flash
| Leaderboard | Gemini 2.5 Flash Preview (09/2025) | Gemini 3.8 Flash |
|---|---|---|
| Epoch Capabilities Index | Not in top 20 | #19 · 157.4 |
Ranks among Noumen catalog models on Epoch AI leaderboards. Only top-20 placements are listed.Epoch AI
- Gemini 2.5 Flash Preview (09/2025)
- Gemini 3.8 Flash
| Leaderboard | Gemini 2.5 Flash Preview (09/2025) | Gemini 3.8 Flash |
|---|---|---|
| ARC-AGI-1 | Not in top 20 | #3 · 98.5% |
| ARC-AGI-2 | Not in top 20 | #10 · 89.2% |
| ARC-AGI-3 (Default harness) | Not in top 20 | #6 · 10.4% |
Ranks among Noumen catalog models on ARC Prize leaderboards. Only top-20 placements are listed.ARC Prize
- Gemini 2.5 Flash Preview (09/2025)
- Gemini 3.8 Flash
| Leaderboard | Gemini 2.5 Flash Preview (09/2025) | Gemini 3.8 Flash |
|---|---|---|
| Game Development | Not in top 20 | #19 · 1305 |
| Website | Not in top 20 | #19 · 1300 |
| UI Component | Not in top 20 | #14 · 1313 |
| SVG | Not in top 20 | #11 · 1292 |
| 3D | Not in top 20 | #20 · 1292 |
| ASCII Art | Not in top 20 | #12 · 1266 |
| Web Apps | Not in top 20 | #12 · 1239 |
| Full Stack | Not in top 20 | #10 · 1244 |
| Mobile Apps | Not in top 20 | #9 · 1235 |
Ranks among Noumen catalog models on Design Arena leaderboards. Only top-20 placements are listed.Design Arena
Live routing data
Performance and reliability
Recent averages across requests routed for this model. Your own speed depends on prompt length, reasoning effort and load.
- Prompt cache hits
- 45.3%
- About $0.18 per 1M input tokens with caching
- Request success (24h)
- 99.7%
- Reliable
Cache hits are the share of input tokens recently served from a prompt cache across all requests. They are not a forecast of your own hit rate.
- Healthy (98% or more)
- Degraded (90–98%)
- Down (under 90%)
- No requests
Developers
Use it through the API
Noumen’s API is OpenAI-compatible: any Chat Completions client works with a base URL and a key.
curl https://www.noumen.xyz/api/v1/chat/completions \
-H "Authorization: Bearer $NOUMEN_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "gemini-2.5-flash-preview-09-2025",
"reasoning_effort": "medium",
"messages": [{ "role": "user", "content": "Explain this stack trace." }]
}'import os
from openai import OpenAI
client = OpenAI(base_url="https://www.noumen.xyz/api/v1", api_key=os.environ["NOUMEN_API_KEY"])
reply = client.chat.completions.create(
model="gemini-2.5-flash-preview-09-2025",
messages=[{"role": "user", "content": "Explain this stack trace."}],
)
print(reply.choices[0].message.content)Related models
Other Google models, starting with the same family.