Google · Efficient
Gemini 3.5 Flash Thinking
Gemini 3.5 Flash with higher thinking enabled for harder reasoning, agentic coding, tool use, multimodal analysis, and long-context workflows. Audio input costs $3.00 per million audio tokens.
- Reasoning
- Vision
- Audio input
- Video input
- Input
- Text, Images, Video, Audio
- Output
- Text
- Reasoning effort
- minimal · low · medium · high
- Discovery tier
- Efficient
Pricing
USD per 1M tokens- Input
- $1.50
- Output
- $9.00
- Cache read
- $0.15
- Cache write
- $0.0833
Reference prices as published by the model provider. API example
Specifications
- Context window
- 1M
- Max output
- 65.5K
- Average output (7 days)
- 1.7K tokens
- Longer than 88% of 465 models
Side by side
Gemini 3.5 Flash Thinking compared
Specifications, prices, speed and benchmark scores next to each other. Benchmarks below show every compared model too.
| Gemini 3.5 Flash ThinkingGoogleThis model | Gemini 3.8 FlashGoogleRemove | |
|---|---|---|
| Provider | ||
| Discovery tier | Efficient | Efficient |
| Added | May 19, 2026 | Sep 2, 2026 |
| Limits | ||
| Context window | 1.05M | 1.05M |
| Max output | 65.54K | 65.54K |
| Average output | 1.7K tokens | 1.2K tokens |
| Pricing, USD per 1M tokens | ||
| Input | $1.50 | $0.75Best |
| Output | $9.00 | $3.75Best |
| Cache read | $0.15 | $0.075Best |
| Cache write | $0.0833 | $0.0417Best |
| Performance | ||
| Throughput | 46.8 tok/s | 223.8 tok/sBest |
| Time to first token | 8.7 s | 7.5 sBest |
| Request success (24h) | 90.1% | 99.8%Best |
| Benchmark indexes | ||
| Intelligence Index | 32.6 | 39.8Best |
| Coding Index | 70.1 | 74.1Best |
| Capabilities | ||
| Reasoning | Yes | Yes |
| Tools | No | Yes |
| Vision | Yes | Yes |
| Structured output | No | Yes |
| PDF input | No | Yes |
| Audio input | Yes | Yes |
| Video input | Yes | Yes |
| Reasoning effort | minimal, 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 3.5 Flash Thinking
- Gemini 3.8 Flash
Intelligence Index
- Gemini 3.5 Flash Thinking32.6
- Gemini 3.8 Flash39.8
Gemini 3.5 Flash Thinking tested at high reasoning effort
Gemini 3.5 Flash Thinking: Better than 76% of 326 scored models
Indexes
Coding Index
Composite of the coding evaluations
- Gemini 3.5 Flash Thinking: 70.1
- Gemini 3.8 Flash: 74.1Top
Agentic work
AutomationBench-AA
Workflow automation, penalized for guardrail violations
- Gemini 3.5 Flash Thinking: 42.1%
- Gemini 3.8 Flash: 60.9%Top
AutomationBench-AA tasks completed
Workflows finished end to end without a guardrail violation
- Gemini 3.5 Flash Thinking: 13.5%
- Gemini 3.8 Flash: 31.1%Top
AA-Briefcasev1.1
Agentic knowledge work, rated head to head
- Gemini 3.5 Flash Thinking: 874 Elo
- Gemini 3.8 Flash: 1,181 EloTop
GDPval-AAv2.1
Economically valuable occupational tasks, rated head to head
- Gemini 3.5 Flash Thinking: 1,202 Elo
- Gemini 3.8 Flash: 1,423 EloTop
Document reasoning
GDP.pdf
Professional reasoning over PDF documents, all-pass rate
- Gemini 3.5 Flash Thinking: 19.8%
- Gemini 3.8 Flash: 22.8%Top
AA-LCRv1.1
Reasoning across long documents
- Gemini 3.5 Flash Thinking: 73.3%
- Gemini 3.8 Flash: 84.0%Top
MLCR-AA
Long-context reasoning over medical records
- Gemini 3.5 Flash Thinking: 10.0%
- Gemini 3.8 Flash: 12.8%Top
Reasoning and knowledge
Humanity’s Last Exam
Expert-level questions across academic fields
- Gemini 3.5 Flash Thinking: 42.7%Top
- Gemini 3.8 Flash: 42.1%
GPQA Diamond
Graduate-level science questions
- Gemini 3.5 Flash Thinking: 92.2%
- Gemini 3.8 Flash: 93.5%Top
IFBench
Following precise output instructions
- Gemini 3.5 Flash Thinking: 76.3%
- Gemini 3.8 Flash: —
Coding
Terminal-Benchv4.0
Practical software engineering in a terminal
- Gemini 3.5 Flash Thinking: 6.6%
- Gemini 3.8 Flash: 19.7%Top
SciCode
Scientific computing in Python
- Gemini 3.5 Flash Thinking: 53.9%
- Gemini 3.8 Flash: 55.1%Top
Legacy evaluations
Terminal-Bench Hard
Earlier terminal task suite
- Gemini 3.5 Flash Thinking: 40.9%
- Gemini 3.8 Flash: —
τ²-Bench Telecom
Tool use in a customer-support simulation
- Gemini 3.5 Flash Thinking: 95.3%
- Gemini 3.8 Flash: —
AA-LCR (unversioned)
Long-context reasoning, earlier grading
- Gemini 3.5 Flash Thinking: 73.3%
- Gemini 3.8 Flash: 84.0%Top
Scores from Artificial Analysis, updated Oct 26, 2026. Gemini 3.5 Flash Thinking was tested at high reasoning effort; compare scores measured at the same effort.Artificial Analysis
- Gemini 3.5 Flash Thinking
- Gemini 3.8 Flash
| Leaderboard | Gemini 3.5 Flash Thinking | 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 3.5 Flash Thinking
- Gemini 3.8 Flash
| Leaderboard | Gemini 3.5 Flash Thinking | 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 3.5 Flash Thinking
- Gemini 3.8 Flash
| Leaderboard | Gemini 3.5 Flash Thinking | Gemini 3.8 Flash |
|---|---|---|
| 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 3.5 Flash Thinking
- Gemini 3.8 Flash
| Leaderboard | Gemini 3.5 Flash Thinking | 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 3.5 Flash Thinking
- Gemini 3.8 Flash
| Leaderboard | Gemini 3.5 Flash Thinking | 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 3.5 Flash Thinking
- Gemini 3.8 Flash
| Leaderboard | Gemini 3.5 Flash Thinking | 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.
- Throughput
- 46.8 tok/s
- Faster than 34% of 250 models
- Time to first token
- 8.7 s
- Quicker than 14% of 250 models
- Prompt cache hits
- 21.3%
- About $1.21 per 1M input tokens with caching
- Request success (24h)
- 90.2%
- Unstable
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": "google/gemini-3.5-flash-thinking",
"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="google/gemini-3.5-flash-thinking",
messages=[{"role": "user", "content": "Explain this stack trace."}],
)
print(reply.choices[0].message.content)Related models
Other Google models, starting with the same family.