overview

2026 年最值得使用的 10 个免费 AI API

📅 2026-08-19 00:00:00 +0000 UTC 👁 9829 浏览 📂 overview

⚠️ 待更新·2026-08-29核验 · 更新时间待核验 · 本文信息可能已过期，请以官方文档为准更新时间：2026-08-29 · 核验状态：待更新 · 官方溯源待补

引言

2026 年的免费 AI API 已经不再是"玩具额度"——它们足以支撑个人开发者把原型一路推到生产边缘，前提是你按"稳定 + 额度慷慨 + 文档完善"三个维度做精选。本文挑出 10 个长期可用的接口，覆盖聊天、绘图、语音三大场景，并给出端点、配额和典型用法。选型策略上，我们刻意混合三种来源：聚合层（OpenRouter、Hugging Face）、硬件云（NVIDIA NIM、Groq）、以及模型实验室直连（Mistral、DeepSeek、Gemini），因为只有跨类别分散才能在某个免费层突然收紧时无缝切换。

flowchart TD Client["Developer Client"] Client --> Chat["Chat / Text APIs"] Client --> Image["Image APIs"] Client --> Voice["Voice APIs"] Chat --> OR["OpenRouter :free"] Chat --> GQ["Groq LPU"] Chat --> DS["DeepSeek V3/R1"] Chat --> MS["Mistral La Plateforme"] Image --> HF["Hugging Face FLUX/SDXL"] Image --> PL["Pollinations URL API"] Voice --> WH["Whisper ASR"] Voice --> ET["Edge-TTS"]

精选清单

OpenRouter — 聚合数百模型，:free 后缀零成本，OpenAI 兼容协议，是免费层的"瑞士军刀"。
NVIDIA NIM — integrate.api.nvidia.com，新用户 1000 credits，覆盖 Llama/Qwen/Mistral/Nemotron，硬件加速延迟低。
Groq — LPU 推理云，llama-3.3-70b-versatile 单秒数百 token，适合实时聊天与语音助手前端。
Hugging Face — InferenceClient 一行调用数万模型，文本/图像/音频全覆盖，是免费层的"实验场"。
Together AI — 新用户 $5 信用额度，覆盖 Llama/Qwen/DeepSeek 权重，价格低于闭源模型。
Google Gemini — gemini-2.0-flash 免费层 10 RPM、日 1500 请求，1M 上下文窗口在免费层中独一份。
Mistral La Plateforme — open-mistral-7b 与 Mixtral MoE 都有免费配额，多语言与代码任务表现稳健。
DeepSeek — deepseek-chat 与 deepseek-reasoner，新用户赠送 token，推理模型尤其适合数学与代码。
Cohere Trial — command-r-plus 试用 Key，月 1000 次，内置 RAG 与 rerank 能力。
Kimi (Moonshot) — 长上下文中文模型试用接口，文档密集型中文场景表现突出。

调用示例

from openai import OpenAI

# 用 OpenRouter 作为统一入口；其他 provider 只需换 base_url + api_key
client = OpenAI(
    base_url="https://openrouter.ai/api/v1",
    api_key="sk-or-..."
)
resp = client.chat.completions.create(
    model="deepseek/deepseek-chat:free",
    messages=[{"role": "user", "content": "用一句话介绍 RAG"}],
)
print(resp.choices[0].message.content)

配额与限流速查

Provider	免费层量级	关键限制	文档
OpenRouter	`:free` 模型无限制	日 50–200 请求/模型	openrouter.ai/docs
Groq	30 RPM / 14400 req/day	单次 prompt ≤ 8K token	console.groq.com/docs
Gemini	15 RPM / 1500 req/day	1M 上下文但需排队	ai.google.dev
NVIDIA NIM	1000 credits 一次性	每模型独立 QPS	docs.nvidia.com
Cohere Trial	1000 calls/月	单次 ≤ 4096 token	docs.cohere.com

最佳实践

免费优先 + 付费兜底：把免费 endpoint 列为主路由，付费 key 设为 fallback；任何免费层突然收紧，路由自动降级。
多 provider 并发：同一请求并发打到 2–3 个免费 endpoint，谁先返回用谁，把延迟方差吃掉。
告警先于限流：为每个 key 设置日配额 70% 告警，提前发现被刷爆的迹象，比收到 429 再处理省事得多。
生产前核对 SLA：免费层没有 SLA，生产前确认你能否承受某个 provider 突然停服 12 小时。
统一网关收口：把所有免费 key 收到一个网关后面（参见 un-01《什么是统一调用 API 网关》），客户端只持有网关 token，方便热轮换和审计。

⚠️ Pending Update · 2026-08-29 Verification · Content may be outdated, please refer to official docs Updated: 2026-08-29 · Status: Pending Verification

Introduction

In 2026, the free AI API landscape has matured to the point where a solo developer can travel from prototype to the edge of production without spending a cent. The challenge is no longer availability — it is curation. Hundreds of endpoints claim to be "free," but only a subset are stable enough, generous enough, and well-documented enough to depend on. This article shortlists ten, judged by long-term stability, free-tier generosity, and documentation quality, so you can pick a small pool rather than gambling on a single provider. The list deliberately mixes pure aggregators (OpenRouter), hardware-backed clouds (NVIDIA, Groq), and model labs with direct APIs (Mistral, DeepSeek, Gemini), because diversifying across these categories is what makes a free-tier strategy resilient — if one category tightens its quota, the others absorb the load.

The Shortlist

OpenRouter — aggregates hundreds of models behind one OpenAI-compatible endpoint. Any model suffixed :free costs nothing, making it the canonical entry point for cost-conscious developers.
NVIDIA NIM — integrate.api.nvidia.com grants 1000 credits to new accounts. Co-designed with NVIDIA hardware, it delivers low latency across Llama, Qwen, Mistral, and Nemotron families.
Groq — LPU-backed inference. llama-3.3-70b-versatile returns hundreds of tokens per second, ideal for real-time chat and voice-assistant frontends.
Hugging Face Inference — InferenceClient reaches tens of thousands of hosted models in one call, covering text, image, audio, and multimodal tasks.
Together AI — $5 credit for new users, covering Llama, Qwen, and DeepSeek weights at prices below closed-model rates.
Google Gemini — gemini-2.0-flash free tier offers 15 RPM and 1500 requests per day, with a 1M-token context window that is rare among free offerings.
Mistral La Plateforme — open-mistral-7b and the Mixtral MoE family ship with a free rate quota, strong on multilingual and code tasks.
DeepSeek — deepseek-chat and deepseek-reasoner grant bonus tokens to new sign-ups; the reasoner is especially strong on math and code.
Cohere Trial Keys — command-r-plus trial key, 1000 calls per month, with built-in retrieval and reranking.
Kimi (Moonshot) — long-context Chinese model with an open trial API, well suited to document-heavy Chinese workloads.

Unified Call Example

from openai import OpenAI

# OpenRouter is the unified entry; swap base_url + api_key for other providers
client = OpenAI(
    base_url="https://openrouter.ai/api/v1",
    api_key="sk-or-..."
)
resp = client.chat.completions.create(
    model="deepseek/deepseek-chat:free",
    messages=[{"role": "user", "content": "Explain RAG in one sentence."}],
)
print(resp.choices[0].message.content)

Quota and Rate-Limit Reference

Provider	Free-tier scale	Key limit	Docs
OpenRouter	`:free` models unlimited	50–200 req/day per model	openrouter.ai/docs
Groq	30 RPM / 14400 req/day	single prompt ≤ 8K tokens	console.groq.com/docs
Gemini	15 RPM / 1500 req/day	1M context, queued	ai.google.dev
NVIDIA NIM	1000 credits one-time	per-model QPS	docs.nvidia.com
Cohere Trial	1000 calls/month	single call ≤ 4096 tokens	docs.cohere.com

Best Practices

Free-first with paid fallback: route to free endpoints first; only fall back to paid keys when free quota is exhausted. If a free tier tightens, routing degrades gracefully.
Fan out across providers: fire the same request to 2–3 free endpoints concurrently and use whichever returns first. This absorbs per-provider latency variance.
Alert before throttle: set a 70%-of-quota alert on every key so you spot abuse before you hit 429.
Verify SLA before production: free tiers have no SLA. Before shipping, confirm you can survive any single provider going dark for 12 hours.
Centralize via a gateway: route all free keys through a unified gateway (see article un-01) so clients hold only a gateway token, enabling hot rotation and audit.