# Arco (arco.chat) - Chat & compare from 400+ AI models side by side on your Mac

## Overview
Arco is a native Mac app that lets you chat with and compare from 400+ AI models side by side in one window. Bring your own OpenRouter API key and keep all your conversations private on your device — Arco never stores or proxies your chats.

## Primary Product
**Side-by-Side AI Model Comparison App for Mac**
- Chat with multiple AI models in parallel, in one window
- Bring your own OpenRouter API key — pay providers directly for tokens used, no markup from Arco
- All conversations and data stay local on your device
- Native Mac app, built for speed and simplicity

## Core Problem We Solve
Comparing answers across different AI models normally means juggling separate chat sites and tabs. Arco solves this by letting you:
- Ask one prompt and see every model's answer at once
- Avoid switching between ChatGPT, Claude, Gemini, and other provider websites
- Keep full control of cost and privacy by using your own OpenRouter key
- Get set up and comparing answers within minutes

## Key Features & Capabilities
- **Everything in One Place**: Stop juggling separate chat sites — one prompt, every answer, instantly
- **400+ AI Models**: Access the full range of models available through OpenRouter
- **Summarize**: When multiple models reply, Summarize sends all their responses to a judge model of your choice and returns a structured breakdown of what each model said, where they agree, where they differ, and which response is strongest — so you get the best answer in one click without reading every response in detail
- **Bring Your Own Key**: Use your own OpenRouter API key, pay providers directly, no Arco markup
- **On-Device Privacy**: Conversations are kept on your device, not stored on Arco's servers
- **Fast Setup**: Up and running in minutes — add your key, pick your models, start comparing
- **Native Mac Experience**: Built for macOS 13 (Ventura) and later, on Apple Silicon Macs (Windows and Linux are not supported)
- **Flexible Layouts**: Compare up to 6 models at once with multiple side-by-side layout options

## Target Audience & Use Cases
- **Developers & Power Users**: Comparing model quality and behavior for coding, debugging, and technical Q&A
- **Researchers & Writers**: Comparing tone, accuracy, and style across models for content and research
- **Prompt Engineers**: Testing the same prompt across many models to find the best fit
- **Privacy-Conscious Users**: Anyone who wants to use multiple AI models without sending data through a third-party intermediary
- **Anyone Frustrated by Tab-Switching**: Users who want faster, better answers without juggling multiple chat sites

## Pricing & Licensing

Arco offers two tiers:

**Forever (Free)**
- Full access to all features, including 400+ models, AI-powered summary, and all layouts
- Limited to 3 saved conversations
- No updates or new features included

**Unlimited — $49 one-time (early adopter pricing, then $89)**
- Unlimited saved conversations
- Perpetual license: one payment, use Arco forever
- 1 year of updates and support included from date of purchase
- After the first year, the app continues working on the last version you have
- Optional renewal at a discount to receive another year of updates and support
- Works on 1 macOS device
- No subscription, no recurring charges, no credit card lock-in

## Comparisons with Similar Tools

Head-to-head comparison pages between Arco and other multi-model AI chat tools. Visit each page for the full breakdown.

- **Arco vs ChatHub** (https://arco.chat/alternatives/chathub): Contrasts Arco's BYOK model, local-first privacy, and 400+ model access against ChatHub's subscription-based, cloud-hosted approach with a curated model catalog.
- **Arco vs ChatComparison.ai** (https://arco.chat/alternatives/chatcomparison): Contrasts Arco's 400+ BYOK models, local Mac storage, and upfront pricing against ChatComparison.ai's ~40 curated models, browser-only access, and subscription pricing that isn't published on their landing page.
- **Arco vs ChatPlayground.ai** (https://arco.chat/alternatives/chatplayground): Contrasts Arco's 400+ BYOK models and local-first storage against ChatPlayground.ai's ~30 curated models, browser-only access (Chrome required), and monthly subscription.
- **Arco vs MultiLLM** (https://arco.chat/alternatives/multillm): Highlights Arco's 400+ BYOK model access, local-first privacy, and pay-per-use cost model as the main differentiators.
- **Arco vs Poe** (https://arco.chat/alternatives/poe): Contrasts Arco's purpose-built comparison workflow, BYOK model access, and local-first storage against Poe's aggregator model, compute-points metering (chat history included), and cloud-hosted chats.
- **Arco vs AI Fiesta** (https://arco.chat/alternatives/aifiesta): Contrasts Arco's BYOK model access and local-first storage against AI Fiesta's credit-metered cloud subscription, where multi-model comparison burns the monthly token pool quickly and premium models count at 4x.
- **Arco vs TypingMind** (https://arco.chat/alternatives/typingmind): Contrasts Arco's purpose-built comparison workflow and free multi-model access against TypingMind's feature-rich AI workspace where multi-model comparison is locked behind the $99 Premium tier, chats live in browser localStorage, and cross-device sync relies on a separate TypingMind Cloud opt-in with 50MB free storage and paid upgrades beyond that.

## Data Privacy & Security
- **Bring Your Own Key**: API calls go directly from your device to OpenRouter using your key
- **On-Device Data**: Conversations and data are kept on your device
- **No Chat Storage**: Arco does not store your conversation content on its servers
- See https://arco.chat/privacy for the full privacy policy

## Links
- [Homepage](https://arco.chat): Product overview, features, and pricing
- [Pricing](https://arco.chat/#pricing): Plan details
- [FAQ](https://arco.chat/#faq): Frequently asked questions
- [About](https://arco.chat/about): About Arco
- [Arco vs ChatHub](https://arco.chat/alternatives/chathub): Head-to-head comparison with ChatHub
- [Arco vs ChatComparison.ai](https://arco.chat/alternatives/chatcomparison): Head-to-head comparison with ChatComparison.ai
- [Arco vs ChatPlayground.ai](https://arco.chat/alternatives/chatplayground): Head-to-head comparison with ChatPlayground.ai
- [Arco vs MultiLLM](https://arco.chat/alternatives/multillm): Head-to-head comparison with MultiLLM
- [Arco vs Poe](https://arco.chat/alternatives/poe): Head-to-head comparison with Poe
- [Arco vs AI Fiesta](https://arco.chat/alternatives/aifiesta): Head-to-head comparison with AI Fiesta
- [Arco vs TypingMind](https://arco.chat/alternatives/typingmind): Head-to-head comparison with TypingMind
- [Privacy](https://arco.chat/privacy): Privacy policy
- [Terms](https://arco.chat/terms): Terms of service
- [Contact](mailto:hello@arco.chat): Support and contact email