Gemini 3.8 Flash TTS
Speech and audio
gemini-3.8-flash-tts
$0.50 in, $9 out per 1M tokens
Gemini 3.8 Flash
Google’s flagship workhorse model (Sept 2026): best Gemini for coding agents, multi-step reasoning and long multimodal context at Flash prices.
Model idgemini-3.8-flash
Price$0.75 in, $3.75 out per 1M tokens
Checked29 September 2026
Knows up to March 2026
1,889events after its cutoff
85 historic, 433 major. 227 days of news.
It launched on 2 September 2026, already missing 290 of them.
How to call it
4 ways to use Gemini 3.8 Flash, with the model id each provider expects.
| Provider | Model id | Endpoint | Docs |
|---|---|---|---|
| Gemini API | gemini-3.8-flash |
https://generativelanguage.googleapis.com/v1beta/models/gemini-3.8-flash:generateContent |
ai.google.dev |
| Google Cloud Gemini Enterprise Agent Platform (Vertex AI) | gemini-3.8-flash |
docs.cloud.google.com | |
| OpenRouter | google/gemini-3.8-flash |
||
| Web app | gemini.google.com |
Pricing
| Input | $0.75 per 1M tokens |
|---|---|
| Output | $3.75 per 1M tokens |
As published: “per 1M tokens (Standard tier, introductory price through 2026-12-31; rises to $1.50 / $7.50 from 2027-01-01)”.
Source: ai.google.dev, checked 29 September 2026.
Specs
- Input
- Text, images, audio, video and PDF
- Output
- Text
- Context window
- 1,048,576 tokens
- Max output
- 65,536 tokens
- Open weights
- No
- Licence
- Proprietary
- Training cutoff
- March 2026
- Released
- 2 September 2026
- Status
- Current
- Type
- Reasoning model
What stands out
What its maker marketed at launch, and what people found later, each with its source.
Long-horizon software engineering
Google’s most capable Flash for autonomous end-to-end engineering; 73.7% on DeepSWE v1.1, 89.4% terminal-based coding per model card.
Specialized-domain agentic analysis
Beats 3.7 Flash and other frontier models on Vals Finance Agent v2 (61.4%) and Harvey’s Legal Agent Benchmark.
Agentic long-video understanding
87.8% long video understanding in agentic mode (agentic video understanding added for 3.x Flash on 2026-09-01).
Adjustable thinking levels + computer use
Thinking low/medium/high, computer use (preview), Maps/Search grounding, flex and priority inference tiers.
Cyber sibling model
Launched alongside Gemini 3.8 Flash Cyber (vulnerability detection/patching, 47.2% CWE-Bench pass@1), available only to vetted defenders via the Fairwind Program.
Four assistants, one scale
Gemini 3.8 Flash is added as a fifth row. Each row runs from what the model knows (graphite) through the months between its cutoff and its launch (hatched) to today (pink).
- GPT-6 Astra 271 at launch, 1,863 today
- Claude Opus 5.5 372 at launch, 1,795 today
- Gemini 4 Hydrogen 1,863 at launch, 1,889 today
- Grok 4.7 387 at launch, 1,829 today
- Gemini 3.8 Flash 290 at launch, 1,889 today
Show as a table
| Model | Cutoff | Released | Missing at launch | Missing today |
|---|---|---|---|---|
| GPT-6 Astra | April 2026 | 3 September 2026 | 271 | 1,863 |
| Claude Opus 5.5 | June 2026 | 22 September 2026 | 372 | 1,795 |
| Gemini 4 Hydrogen | March 2026 | 12 November 2026 | 1,863 | 1,889 |
| Grok 4.7 | May 2026 | 21 September 2026 | 387 | 1,829 |
| Gemini 3.8 Flash | March 2026 | 2 September 2026 | 290 | 1,889 |
Notes
Newest and recommended Gemini text model as of 2026-09 (no Pro newer than 3.1 Pro preview; 3.5 Pro announced but unreleased). Aliases gemini-flash-latest may point here. Model card says some domains’ knowledge only to 2025-01. Vertex id inferred from docs page.
curl "https://generativelanguage.googleapis.com/v1beta/models/gemini-3.8-flash:generateContent" \
-H "x-goog-api-key: $GEMINI_API_KEY" -H "Content-Type: application/json" \
-d '{"contents":[{"parts":[{"text":"Explain how AI works in a few words"}]}]}'
Sources: model page, pricing, launch blog, model card.