Aider vs Windsurf: Which AI Agent Is Better?
An in-depth comparison of Aider and Windsurf across output quality, autonomy, reliability, speed, value, and ease of use. Vote for your favorite.
An in-depth comparison of Aider and Windsurf across output quality, autonomy, reliability, speed, value, and ease of use. Vote for your favorite.
Either way, you pay for the model calls. A median coding-agent day on our gateway is 95 requests and 8.6 million tokens. The table prices every step at one model’s rate.
Aider runs on Standard Compute, where each step goes to the cheapest model that can do it: routine steps go to efficient open models, hard ones to frontier models such as Claude Fable 5.1 or GPT-6 Astra.
| Model | Typical day | Busy day |
|---|---|---|
| Claude Opus 5.5 | $7.34 | $59.10 |
| Claude Sonnet 5.5 | $3.67 | $29.55 |
| GPT-6 Luna | $0.23 | $2.43 |
Fixed monthly plans from $19. Eligible new accounts can try $0.25 of compute first, no card. Trial terms
Pick a winner in each category. You can change your vote anytime.
AiderWindsurfChoose Aider if you are developers who want a flexible, BYO-model terminal coding tool. Choose Windsurf if you are developers who want an affordable AI editor with agentic capabilities.
Editorially this matchup is a dead heat: each agent leads in 3 of our six categories. On price, Aider runs free (byo api key) and is open source; Windsurf runs free / $20 pro / $200 max (as devin desktop) and is proprietary.
What it costs to run Aider
Best API for Aider →
5 options compared, with prices and limits
Standard Compute sends each step to the cheapest model that can do it, on providers we vet for price, uptime and speed. Plans start at $19 a month, and eligible new accounts can try $0.25 of compute with no card. Choose your agent below to connect.
Aider is an open-source (Apache 2.0) AI pair programming tool that works in your terminal. It can edit multiple files, understand your git history, create commits, and works with virtually any LLM via API. It earned its reputation with a practical approach to real-world coding tasks and strong benchmark scores, but development has gone quiet: the last release was 0.86.2 in February 2026 and the last commit came in May 2026.
Windsurf began as Codeium's AI-first code editor, known for its Cascade agent. Cognition (the company behind Devin) bought it in 2025, and since June 2026 it ships as Devin Desktop, "the next generation of Windsurf": an agent command center with a built-in VS Code-style IDE; windsurf.com now redirects there. Plans are shared with Devin: Free, Pro at $20 a month and Max at $200, each with a usage allowance that refreshes daily and weekly, and extra usage billed at API prices.
Aider runs on Standard Compute
