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Anthropic Google OpenAI

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Anthropic 29 Google 24 OpenAI 103
Google gemini-2.5-flash-lite-preview-09-2025

Gemini 2.5 Flash-Lite (preview 09-2025) (Google)

Retired

Yes — Gemini 2.5 Flash-Lite (preview 09-2025) is retired. Google shut it down on March 31, 2026; API requests to it now fail. The recommended replacement is Gemini 3.1 Flash-Lite.

A September 2025 preview of the Flash-Lite tier, notable mainly for its id format: it used a four-digit year where every other Gemini preview uses two. Shut down March 2026.

The facts

Provider Google
Model id gemini-2.5-flash-lite-preview-09-2025
Released September 25, 2025
Deprecated date not published
Shutdown March 31, 2026 · 121 days ago
Status Retired
Last verified July 30, 2026

What to use instead

Google Gemini 3.1 Flash-Lite gemini-3.1-flash-lite Provider-recommended Shutdown scheduled

Google routes this straight to the 3.1 Lite tier rather than to the stable 2.5 Flash-Lite, which is itself scheduled for October 2026.

What parameters gemini-3.1-flash-lite accepts on modelparams.dev

Change the id

In most cases the migration is one string. Check the parameter differences before you ship — newer models drop older sampling knobs more often than they add them. 

- "model": "gemini-2.5-flash-lite-preview-09-2025"
+ "model": "gemini-3.1-flash-lite"

Frequently asked questions

When did Google Gemini 2.5 Flash-Lite (preview 09-2025) shut down?
Google Gemini 2.5 Flash-Lite (preview 09-2025) shut down on March 31, 2026. API requests to it fail from that date onward.
What replaces Google Gemini 2.5 Flash-Lite (preview 09-2025)?
Google recommends Gemini 3.1 Flash-Lite (`gemini-3.1-flash-lite`) as the replacement for Google Gemini 2.5 Flash-Lite (preview 09-2025). Google routes this straight to the 3.1 Lite tier rather than to the stable 2.5 Flash-Lite, which is itself scheduled for October 2026.
Is Google Gemini 2.5 Flash-Lite (preview 09-2025) still available?
No. Google Gemini 2.5 Flash-Lite (preview 09-2025) is retired and no longer served — it was shut down on March 31, 2026. Calls to it return an error.
How do I migrate from Google Gemini 2.5 Flash-Lite (preview 09-2025) to gemini-3.1-flash-lite?
Swap the model id in your API call: replace "gemini-2.5-flash-lite-preview-09-2025" with "gemini-3.1-flash-lite". Google routes this straight to the 3.1 Lite tier rather than to the stable 2.5 Flash-Lite, which is itself scheduled for October 2026.

Sources

Found something wrong? The data is one YAML file — edit it on GitHub.

This page, for machines

JSON Markdown Badge JSON

Drop the badge in a README so it turns red the day this model is retired:

[![gemini-2.5-flash-lite-preview-09-2025](https://img.shields.io/endpoint?url=https://modeldeprecations.dev/badge/google/gemini-2.5-flash-lite-preview-09-2025.json)](https://modeldeprecations.dev/google/gemini-2.5-flash-lite-preview-09-2025)

Other Google models

All Google deprecations →

How to use this site

The full guide, in Markdown. Copy it and hand it to a coding agent verbatim.

# How to use modeldeprecations.dev

[modeldeprecations.dev](https://modeldeprecations.dev) answers one question per model: is it deprecated,
when does it shut down, and what replaces it. Every date on the site is cited to the
provider's own documentation, with the date we last checked it.

Three lifecycle states are used, matching the providers' own vocabulary:

- **active** — still supported, no deprecation announced.
- **deprecated** — the provider has announced it is going away. It still answers requests.
- **retired** — API access is gone. Requests fail.

A model can be active *and* carry a shutdown date: Anthropic publishes a
"not sooner than" date and Google publishes an earliest shutdown date for models
that are current and fully supported. Those are reported as scheduled shutdowns,
not deprecations, because that is what the provider actually committed to.

## Check one model

```bash
curl https://modeldeprecations.dev/api/v1/models/openai/gpt-4-32k.json
```

Or fetch the page as Markdown, which includes the answer, the dates and the sources:

```bash
curl https://modeldeprecations.dev/openai/gpt-4-32k.md
```

## Full catalog

```bash
curl https://modeldeprecations.dev/api/v1/models.json
```

Ids are `provider/model`. Dated snapshots (`gpt-4-32k-0613`) are listed as aliases of
their canonical entry rather than as separate records.

Each entry carries `computed_status`, the lifecycle state recomputed against the build
date — so a model whose shutdown has passed reads `retired` without anyone editing data.

## Badges

A shields.io endpoint per model, for READMEs that should go red when a model dies:

```
https://img.shields.io/endpoint?url=https://modeldeprecations.dev/badge/openai/gpt-4-32k.json
```

## Calendar and changelog

- Subscribe to every shutdown date: https://modeldeprecations.dev/calendar.ics
- Changelog RSS: https://modeldeprecations.dev/changelog.xml

## JSON Schema

```bash
curl https://modeldeprecations.dev/api/v1/schema.json
```

## Contribute

Data lives in YAML under `models/{provider}/{model}.yaml` in the
[GitHub repo](https://github.com/mnfst/modeldeprecations.dev). Every lifecycle date needs a source URL; CI rejects a
date without one. Open a PR.

## For agents

- Machine-readable overview: https://modeldeprecations.dev/llms.txt
- This guide plus every model inline: https://modeldeprecations.dev/llms-full.txt
- Any page also exists as Markdown: append `.md` to a model URL.
- In a browser, this site registers a **WebMCP** tool on `navigator.modelContext`:
  `check_model_deprecation`, `list_shutdowns`, `find_replacement`, and `get_usage_guide`.
- Parameters each model accepts are catalogued on the sibling site, https://modelparams.dev.