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Free LLM Playground

Try top LLM models from the best AI providers (ChatGPT, Gemini, Claude, and more) in a single LLM playground for free. Share results in one click. No signup, no API keys.

Suggest a comprehensive strategy for a ProductHunt launch
Create 10 Github tickets based on the following template
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* Free: up to 50 chats/day. Resets daily.
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400+ users use our LLM playground weekly
❝ This is the best LLM Playground and I tested so many! So much better than other playgrounds. Everything is right at hand when you need it. ❞
Roberta Sorokroy
Roberta SorokroyProduct Manager at Yola.com
No SignupNo API keysNo Training on Your Data50 Free Chats/Day20+ LLMsInstant SharingNo SignupNo API keysNo Training on Your Data50 Free Chats/Day20+ LLMsInstant Sharing

Why Free LLM Playground?

Start instantly.

No signup. No API keys.
Just type and run.

Compare models.

Across OpenAI, Anthropic, Gemini & open-weights.

Run with variables.

Jinja2 templates and inputs for real-data testing.

Share & replay.

Public links, transcripts, and cURL/JS export.

Private by default.

We don't train on your prompts and data.

Scales with you.

Buy more volume when you need.

Why Us over other LLM Playgrounds?

Other playgroundsFrom VC-baked companies

Sign up and waste time on Sales demo calls
Super confusing dashboard
Requires a lot of configuration
Enterprise plans start at $12K
No support for startups and small teams
VC-baked (optimized for investor returns)

LLM PlaygroundPowered byLangFast

Instant access. No signup, no API keys required
Simple UX designed for each use case
Everything works out-of-box
Use it for free with a fair-use throttling
Stellar support for everyone
Bootstrapped (optimized for customer UX)

Explore All Features

  • Supported AI Models

  • GPT-5
  • GPT-5 Mini
  • GPT-5 Nano
  • GPT-5 Nano
  • GPT-4.5 Preview
  • GPT-4.1
  • GPT-4.1 Mini
  • GPT-4.1 Nano
  • GPT-4o
  • GPT-4o Mini
  • O1
  • O1 Mini
  • O3
  • O3 Mini
  • O4 Mini
  • GPT-4 Turbo
  • GPT-4
  • GPT-3.5 Turbo
  • Claude AI Models (soon)
  • Gemini AI Models (soon)
  • Model Fine-tuning (soon)
  • Model configuration

  • Custom System Instructions
  • Reasoning Effort Control
  • Stream Response Control
  • Temperature Control
  • Presence & Frequency Penalty
  • User Interface

  • Customizable Workspace
  • Wide Screen Support
  • Hotkey & Shortcuts
  • Voice Input (soon)
  • Text-to-Speech (soon)
  • Playground Experience

  • Prompt Library
  • Prompt Templates & Variables
  • Jinja2 Templates Support
  • Upload Documents (soon)
  • Language Output Control
  • Parallel Chat Support
  • Prompt Management

  • Prompt Folders
  • Edit & Fork Prompts
  • Prompt Versioning
  • Upload Documents (soon)
  • Share Prompts
  • Cost & Performance

  • Cost estimation
  • Token usage tracking
  • Context length indicator
  • Max token settings
  • Security and Privacy

  • Private by Default
  • API Tokens Cost Estimation
  • No chats used for training

    Integrations

  • Web Search & Live Data (soon)
  • Plugins

  • Custom Plugins (soon)
  • Image search plugin (soon)
  • Dall-E 3 (soon)
  • Web page reader (soon)

Frequently Asked Questions

What is a free LLM playground?

A free LLM playground is a browser UI to test large language models instantly—no setup, no API keys—built for product managers, engineers, data scientists, and writers who want fast prompt experiments without touching SDKs or billing.

Type a prompt and stream a response, then switch or compare models side-by-side; you can save/share a link, export to cURL/JS/JSON, and use templates or variables, with clear free caps (e.g., 50 chats/day) and optional Pro or Team plans to lift limits.

You get access to all major models for the top LLM providers: OpenAI/GPT (e.g., GPT-4o family or lighter variants), Anthropic/Claude (e.g., Haiku/Sonnet tiers), Google/Gemini (e.g., Flash/Pro variants), Meta Llama (e.g., Llama 3.x, 8B/70B), Mistral/Mixtral, an others.

No. You can start immediately. Keys are optional for power users.

Yes. You get 50 chats/day with fair-use throttling. No signup, no card required. We hope that eventually you will get enough value to transition to a Pro or Team workspace.

See "Supported models." Some premium models may require an upgrade to Pro workspace.

We stream tokens through a tiny proxy layer to ensure you can use it without your own API keys. Typical first token time is low fraction of a second. Speed varies by model/load.

Depends on the model (e.g., 8K–200K tokens). We show it next to each model.

Yes, as long as they are supported by the model itself.

Yes. You can open as may chat tabs as you want see multiple models answer the same prompt.

Yes. Use "Share" button to manage sharing permissions. You can create public URLs or share access with specific email addresses.

No. We don't use your prompts for training. You control retention in Settings.

We route to model providers; see the Data & Privacy page for regions and details.

Generally yes, subject to each model's terms. We link those on the model picker.

Wait for the daily reset or upgrade to Pro workspace to add more volume or your own keys.

Yes, you can if you're on a Team plan. Just reach out to us, and I'll make it happen.

Yes: shared workspace, unlimited requests, bring your own keys, SSO, and centralised billing.

Yes. Reach out to us to get more information.

Yes—share read-only links, export cURL/JS/JSON to replicate calls, and use Bring Your Own Keys (BYOK) to keep the UI while routing costs to your provider.

A free LLM playground is point-and-click for quick evaluation with limited quotas, while paid LLM APIs provide programmatic control, higher throughput, predictable limits, and SLAs for production—use the playground to find prompts/models, then ship with APIs.

As an OpenAI Playground alternative and Hugging Face Spaces alternative, this free LLM playground focuses on instant multi-provider testing (no keys to start), consistent UI, side-by-side comparisons, share links, exports, and transparent free limits in one place.

Wall of love
Join 400+ Happy Users
Rubik
Rubik@Rubik_design
Happy that @eugenegusarov built @langfast. This is the best LLM Playground and I tested so many!So much better than other playgrounds. Everything is right at hand when you need itLangfastAug 24, 2025
CodeZera
CodeZera@codezera11
That's exactly the kind of tool AI devs need in production. Prompt testing is the new debugging, and it eats up real time.Jul 17, 2025
Adrian
Adrian@shephardica
I've felt this pain in my day job - testing and validating prompts is currently difficult, error prone, and just not polished. Great problem to solve 👍Jul 13, 2025
Sasha Reminnyi
Sasha Reminnyi 🇺🇦Founder at Growth Kitchen
Great, had similar idea since launch of GPT, thanks for making that alive 🙏Aug 3, 2025
Glib Ziuzin
Glib ZiuzinFounder BUD TUT
Excited for this 🔥Jul 14, 2025
Rajiv Dev
R𝗮𝗷𝗶𝘃.𝗱𝗲𝘃Jul 17, 2025
I saw your app yeah that was usefullJul 17, 2025
Ship prompts that pass the tests
Don't wait until they break in production
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