The Cloudflare AI Playground at playground.ai.cloudflare.com is a browser environment for experimenting with, benchmarking and tuning AI models, with a Model mode for testing system prompts and run settings, a Compare mode for side-by-side evaluation of models under identical prompts, and an experimental Generative UI mode. It is the front end for models that Cloudflare hosts and serves, and the free access terms come from Workers AI: the free allocation allows anyone to use a total of 10,000 Neurons per day at no charge, with additional usage on the Workers Paid plan billed at $0.011 per 1,000 Neurons. The model catalog covers 65 models including Llama, Qwen, DeepSeek, Kimi, GLM, Gemma, Mistral, Nemotron, Whisper and FLUX families, and the playground itself states that output is unverified and does not reflect Cloudflare's views.

Free allocation is stated as 10,000 Neurons per day at no charge on the Workers AI pricing page, equivalent to about $0.11/day at the published rate of $0.011 per 1,000 Neurons (the dollar figure is a conversion, the allowance is official).

Devin, built by Cognition, is an agentic software engineering product spanning Devin Desktop, a CLI, Devin Cloud agents, DeepWiki and the Devin API, aimed at multi-repo engineering work such as migrations, PR review, incident triage and scheduled chores. Its pricing page lists Free at $0 with "a light quota to code with agents", limited model availability, unlimited inline edits and unlimited Tab completions, then Pro at $20/month, Max at $200/month for significantly higher quotas, Teams at $80/month for the team plan plus $40/month per full dev seat, and Enterprise by contact. Paid plans come with a usage allowance that refreshes daily and weekly, and usage beyond the allowance is purchased and consumed at API pricing.

Devin Free is $0 with a light agent quota, limited model availability, unlimited inline edits and unlimited Tab completions (devin.ai/pricing, checked 2026-09-16).

AI Horde (Stable Horde) is a free, volunteer-run, community-powered network of donated GPUs that generates AI images (Stable Diffusion, SDXL, Flux and other diffusion models) and text. Anonymous access is available with the shared key 0000000000 at lowest priority; registering for kudos raises priority.

Free kudos-based system; no quantified monthly USD credit.

Auggie is Augment Code's free, terminal-based agentic coding CLI (npm i -g @augmentcode/auggie) that runs context-aware agents locally with interactive and headless modes. It is multi-model (Claude, GPT, or bring-your-own-key); the broader Augment 'Cosmos' platform is the company's enterprise offering.

Free CLI tier; enterprise/Cosmos pricing not publicly quantified on the fetched pages.

Chipotle 'Pepper' is the free, anonymous customer-support chatbot on amelia.chipotle.com, powered by IPsoft Amelia. It requires no login (anonymous sessions) and answers only Chipotle-related questions; off-topic prompts are refused.

Free anonymous support chatbot; no credit system.

no-auth access — no key or sign-in required. Authentication is owned by the official Devin CLI in its isolated bridge volume. This entry is an access surface/agent — it routes to third-party models rather than hosting its own.

A free tier is available; the exact credit value is not quantified.

Duck.ai is DuckDuckGo's free, private AI chat (also surfaced at duckduckgo.com/duckchat). It requires no account and offers chat, voice, image, and search across models including OpenAI GPT (e.g., '5.6 Luna') and Claude.

Free anonymous chat; an 'Upgrade'/Pro option exists but pricing not quantified on fetched pages.

Felo (felo.ai) is a free, no-signup multilingual AI search and creation platform for chat, web search, and content generation. It exposes frontier models (e.g., GPT-6 Astra) and offers a paid Pro tier for heavier usage.

Free no-signup tier; Pro subscription pricing not quantified on fetched pages.

OpenAI Codex CLI — OpenAI's terminal coding agent (also web/IDE). Authenticates via ChatGPT OAuth or an API key. Model lineup (as of mid-2026): GPT-6 Astra, GPT-5.6 (Sol/Terra/Luna), GPT-5.5, GPT-5.4 / 5.4 mini, plus gpt-oss-120b; GPT-5.3-Codex-Spark is a Pro-only research preview. Plans: Free, Go ($8), Plus ($20), Pro 5x ($100) / 20x ($200); API-key mode is pay-as-you-go at API rates.

ChatGPT plans use credit-based usage allowances (credits per 1M tokens, e.g. GPT-5.6 Sol 100/10/500); not a fixed $ credit value. API-key mode billed at standard OpenAI API token rates.

no-auth access — no key or sign-in required. No API key required — uses OpenCode's public free endpoint. This entry is an access surface/agent — it routes to third-party models rather than hosting its own.

A free tier is available; the exact credit value is not quantified.

OpenCode Zen is the model gateway from the OpenCode team that serves a curated, tested set of coding models. It includes a set of free models (Big Pickle, MiMo-V2.5 Free, Ling 3.0 Flash Fin Free, Nemotron 3 Ultra Free, Nemotron 3.5 Lightning Free, Muse Spark 1.3 Contributor Free) plus pay-as-you-go paid models, reachable at https://opencode.ai/zen/v1.

Free models are genuinely $0 per token (documented); no separate monthly USD credit.

TheOldLLM (theoldllm.vercel.app) is a free, browser-based multi-model AI workspace for comparing leading models, chat, file/image analysis, web research, and study tools. Standard models need no account; frontier-tier models require a verified email, and rate limits apply.

Free chat interface; access/rate limits vary by account status, no USD credit.

UncloseAI (uncloseai.com) is a free, public-domain, open-source AI service offering OpenAI-compatible, drop-in endpoints with no cost: hermes.ai.unturf.com/v1 (general chat), qwen.ai.unturf.com/v1 (coding), and speech.ai.unturf.com/v1 (TTS). It currently serves Lorbus/Qwen3.6-27B-int4-AutoRound.

Completely free; no credit system.

VEO AI Free (veoaifree.com) is a free, no-signup web tool that generates videos using Google Veo (claims Veo 2.0/3.0/3.1) plus an image generator. It advertises unlimited free use but is an unofficial third-party site (share-to-unlock, ads, and a $14/mo premium plan); the dataset reports ~6 requests/hour/IP.

Free no-signup video generation; premium $14/mo plan exists; no quantified free credit.

ZCode is Zhipu's official coding client for the GLM Coding Plan sold on bigmodel.cn, whose personal tiers are listed in CNY: ¥94.4/month (list ¥118) with 10,000 credits per week, ¥430.4/month (list ¥538) at six times the Lite allowance, and ¥862.4/month (list ¥1078) at fourteen times, each unlocking Claude Code, Codex, Cursor, OpenCode, Cline, Kilo Code and AutoClaw, with ZCode subscribers receiving 150% quota. The platform's API price list shows GLM-5.3 at 8 CNY per million input tokens and 28 CNY output, GLM-5.3-Flash at 0.8/2.8 CNY, GLM-TTS at 2 CNY per 10,000 characters, and Batch calls at half the standard price. New registered users receive 20 million tokens, and GLM-4.7-Flash (200K context) and GLM-4.6V-Flash are listed as free API models.

Allowance is 20,000,000 tokens for newly registered users ('新用户注册得 2000万 Tokens') plus up to 200 million tokens via referral on bigmodel.cn/pricing; no CNY or USD cash value is stated for the grant (checked 2026-09-16).