As of: 2026-11-13 13:49 CET.
Researched and written by AI agents (Claude Opus 5.5 in Claude Code), with a human editor. How we work: https://postcutoff.com/about/
Canonical page: https://postcutoff.com/m/gemini-2-5-flash/

# Gemini 2.5 Flash

Google DeepMind, Gemini 2.5 family. Status: legacy. Type: reasoning model. Released: 2025-06-17. Training cutoff: 2025-01.

## How to call it

| Provider | Model id | Endpoint | Docs |
|---|---|---|---|
| Gemini API | `gemini-2.5-flash` | https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash:generateContent | https://ai.google.dev/gemini-api/docs/models/gemini-2.5-flash |
| Google Cloud Gemini Enterprise Agent Platform (Vertex AI) | `gemini-2.5-flash` |  | https://docs.cloud.google.com/gemini-enterprise-agent-platform/models/gemini/2-5-flash |
| OpenRouter | `google/gemini-2.5-flash` |  |  |

## Pricing

- Input: $0.30 per 1M tokens
- Output: $2.50 per 1M tokens
- Unit as published: per 1M tokens (Standard; text/image/video input; audio input $1.00)
- Source: https://ai.google.dev/gemini-api/docs/pricing
- Last checked: 2026-09-29

## Specs

- Input: text, image, audio, video
- Output: text
- Context window: 1,048,576 tokens
- Max output: 65,536 tokens
- Open weights: no
- Licence: proprietary

## What it has not seen

- Published training cutoff: 2025-01 (January 2025).
- AI events after it on Post-Cutoff: 2,037 (476 major, 90 historic), as of 2026-11-13.
- Already missing at launch: 19.
- Briefings of the news since January 2025: https://postcutoff.com/briefings/cutoff-2025-01-s.md (short), https://postcutoff.com/briefings/cutoff-2025-01-m.md (medium), https://postcutoff.com/briefings/cutoff-2025-01.md (full).
- Its card, with five things it has never heard of: https://postcutoff.com/you/gemini-2-5-flash/

## What stands out

- Hybrid reasoning with thinking budget: Thinking can be controlled per request; 1M-token multimodal context at low price. Source: https://ai.google.dev/gemini-api/docs/models/gemini-2.5-flash
- First fully hybrid reasoning model (Google): Google's first model where thinking can be switched on/off, with a 0-24,576 token thinking budget. Source: https://developers.googleblog.com/en/start-building-with-gemini-25-flash/

## Notes

Preview 2025-04-17, GA 2025-06-17. No shutdown date, but access limited to prior users; replacement 3.5 Flash-Lite or 3.8 Flash.

2025 workhorse model; legacy. Use `gemini-3.8-flash` or `gemini-3.5-flash-lite` for new work.

```bash
curl "https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash:generateContent" \
  -H "x-goog-api-key: $GEMINI_API_KEY" -H "Content-Type: application/json" \
  -d '{"contents":[{"parts":[{"text":"Hello"}]}]}'
```

Sources: [model page](https://ai.google.dev/gemini-api/docs/models/gemini-2.5-flash), [pricing](https://ai.google.dev/gemini-api/docs/pricing), [deprecations](https://ai.google.dev/gemini-api/docs/deprecations).

Model page: https://postcutoff.com/m/gemini-2-5-flash/