OpenCode vs GitHub Copilot vs Claude Code: The June 2026 Coding Agent Rankings

OpenCode crossed 176,000 GitHub stars in June 2026 while GitHub Copilot switched to per-credit billing on June 1 — making this the first month where the three-way cost and performance calculus between OpenCode, Copilot, and Claude Code actually matters for individual developers and engineering teams. Here is what our 8-task benchmark on a real Next.js 15 codebase found.

What Changed in Q2 2026 That Makes This Comparison Different

Three events landed close enough together to reset the comparison:

First, OpenCode reached 176,000+ GitHub stars (MIT) and 1.68 million weekly npm downloads — becoming the most-starred open-source coding agent on GitHub, ahead of Gemini CLI (105,000 stars) and OpenAI’s Codex CLI (89,000 stars). Unlike Cursor or Copilot, OpenCode is a terminal-first agent with no IDE dependency and support for 75+ model providers out of the box.

Second, GitHub Copilot ended flat pricing on June 1, 2026. Every plan now runs on GitHub AI Credits, where one credit equals $0.01. Code completions remain unlimited, but anything involving the agent, chat, code review, or Copilot CLI draws from a monthly credit pool. The Copilot Pro plan ($10/month) includes $10 in credits — meaning a single day of heavy agent use can exhaust your monthly allowance.

Third, Anthropic expanded Claude Code’s pricing tiers to match real usage patterns: Pro at $20/month, Max 5x at $100/month, and Max 20x at $200/month. Anthropic’s internal data shows the average Claude Code user costs ~$6 per day, with 90% staying under $12/day — which means heavy daily users outpace the Pro plan within a week.

The Test Setup: 8 Engineering Tasks on a Real Next.js 15 Codebase

We ran all three agents against the same 8-task suite on a real Next.js 15 + Prisma codebase (~180 files, ~28,000 lines of TypeScript). Tasks ranged from straightforward to multi-file rewrites:

1. Bug fix: resolve a race condition in a React Server Component data fetch
2. API integration: wire a Stripe webhook handler to a Prisma event log
3. Refactor: migrate a 400-line class component to React hooks
4. Test generation: write Vitest unit tests for a utility module (8 functions)
5. PR review: flag issues in a 6-file diff adding role-based access control
6. Documentation: generate JSDoc for 22 exported functions across 3 files
7. Repo-wide rename: update a deprecated API surface across 12 files
8. Greenfield feature: scaffold a new Next.js App Router route with server action and optimistic UI

Scoring: task completion accuracy (did it actually work without manual correction?), files touched beyond the task scope, and whether the test suite still passed afterward.

Benchmark Results: How All Three Agents Performed

OpenCode: The Open-Source Agent That Hit 176,000 GitHub Stars

OpenCode launched in June 2025 and reached 176,000+ GitHub stars in under a year — faster adoption than Gemini CLI (105,000) and OpenAI Codex CLI (89,000). It is MIT-licensed, installs via npm i -g opencode, and runs entirely in the terminal. Its defining advantage is provider neutrality: it connects to any of 75+ LLM providers including Anthropic, OpenAI, Google, Mistral, and self-hosted Ollama models.

In our test suite, OpenCode running Claude Sonnet 4.6 via direct API completed 6/8 tasks cleanly. It struggled on the repo-wide rename task — touching 12 files correctly but introducing a stale import reference in a 13th file it had not been given context about. This is the core OpenCode limit: it excels on greenfield code and single-file work, but its context window management on large monorepos (200+ files) requires deliberate scoping from the operator.

“OpenCode ships daily and supports 75-plus providers,” per the OpenCode GitHub README. At 1.68 million weekly npm downloads, it is the most actively installed open-source coding agent as of June 2026.

Cost math: running OpenCode with Claude Sonnet 4.6 at $3 per million input tokens and $15 per million output tokens, our 8-task suite cost $2.14 in API fees. At moderate daily use (~3 sessions/day), expect $15–35/month in Sonnet 4.6 API spend — less than Copilot Pro+ and with no credit surprises.

GitHub Copilot: Capable IDE Integration, Confusing New Credit Math

GitHub Copilot Pro+ ($39/month) remains the strongest IDE-integrated option — inline completion, multi-file agent mode, PR review, and Copilot CLI are all in one subscription. Its June 2026 rebilling to AI Credits adds a layer of unpredictability that matters for teams doing heavy agent work.

Code completions and Next Edit Suggestions remain unlimited and consume no credits. But every chat message, agent mode session, code review request, and CLI invocation now draws from the credit pool. The Pro+ plan’s $39 monthly credit allocation sounds generous until you run agent mode on a large PR — a single complex agent session can consume $2–5 in credits, which is 5–13% of a Pro+ user’s monthly budget in one sitting.

In our benchmark, Copilot Pro+ using GPT-5 completed 5/8 tasks. It failed the race condition bug fix (produced a valid-looking patch that introduced a new state inconsistency) and the repo-wide rename (missed two usages in dynamically imported modules). Its test generation output was the cleanest of the three — structured, well-named, high coverage — but required manual correction on 2 of the 8 Vitest cases.

As we noted in our Claude Code vs Cursor comparison, the IDE-first agents consistently outperform terminal agents on the daily completion workflow — the real question is whether you are paying for that integration via a subscription or via API tokens.

Claude Code: Best Raw Output Quality, Highest Context Budget Consumption

Claude Code Pro ($20/month, $17/month annual) produced the highest task pass rate in our benchmark — 7/8 tasks, with all 8 post-task test suite runs passing. The one failure was the PR review task: Claude Code flagged 4 of 6 real issues in the RBAC diff but missed a privilege escalation path introduced by an incorrectly scoped middleware check.

The quality ceiling is real. Claude Code’s output on the React hooks refactor was the only one of the three that preserved every subtle side effect from the class lifecycle methods while simultaneously simplifying the component API. No post-run corrections required.

The cost ceiling is also real. Claude Code Pro’s usage limit is calibrated for moderate daily use. Anthropic’s own data shows 90% of users stay under $12/day — but a single repo-wide refactor session on a 28,000-line codebase can hit that limit in under two hours. On the Max 5x plan ($100/month), the context budget is enough for 5–6 heavy sessions per day; Max 20x ($200/month) is what full-time autonomous agents require.

Terminal-Bench 2.1 ranks Claude Code with Opus 4.8 at 78.9%, second only to Codex CLI with GPT-5.5 at 83.4%. For the real-world quality tasks that make up typical developer work (the ones not well-captured by benchmark harnesses), our subjective assessment matches the quantified scores: Claude Code produces the most correct and the most readable output of the three.

Which Coding Agent Should You Actually Use?

The right choice depends on your workflow more than your budget:

• Use OpenCode if you are self-directed, comfortable in the terminal, work on projects under 150 files, and want to route different task types to different models. The API cost transparency and provider flexibility make it the best fit for solo developers and researchers.
• Use GitHub Copilot (Pro or Pro+) if your team is already on GitHub, you spend most of your day in VS Code or JetBrains, and your agent usage is light-to-moderate. Track your credit consumption weekly for the first month — the new billing model can surprise teams that use agent mode heavily.
• Use Claude Code if output quality is non-negotiable, you are doing deep refactors or complex multi-file work, and you can budget for Max 5x or above. On the Pro plan, you will hit usage limits mid-sprint.

Is OpenCode free to use?

OpenCode is free to install and run — it is MIT-licensed open-source software. You pay only for the model API you connect to it. Using OpenCode with Claude Sonnet 4.6 costs $3 per million input tokens and $15 per million output tokens via the Anthropic API. Typical moderate daily use runs $15–35 per month in API fees.

How does GitHub Copilot’s new credit system work in 2026?

As of June 1, 2026, GitHub Copilot runs on AI Credits — one credit equals $0.01 USD. The Pro plan ($10/month) includes $10 in credits; Pro+ ($39/month) includes $39. Code completions and Next Edit Suggestions remain unlimited and consume no credits. Chat, agent mode sessions, code review requests, and Copilot CLI invocations do consume credits based on token usage. You can purchase additional credits when your monthly pool is exhausted.

What is Claude Code’s monthly limit on the Pro plan?

Anthropic does not publish a hard token cap for Claude Code Pro ($20/month). Instead, the plan is calibrated for moderate daily use — Anthropic’s internal data shows 90% of users stay under $12/day in equivalent API cost. Developers doing heavy daily sessions (large refactors, repo-wide changes, long context tasks) typically outgrow the Pro plan within a week. The Max 5x plan ($100/month) is the practical next step for full-time Claude Code users.

Where does OpenCode rank on the Terminal-Bench 2.1 leaderboard?

OpenCode itself is a multi-model agent framework — its benchmark ranking depends on which model you connect to it. On Terminal-Bench 2.1, Codex CLI with GPT-5.5 ranks first at 83.4%, and Claude Code with Opus 4.8 ranks second at 78.9%. Running OpenCode with Sonnet 4.6 produces results in a comparable range to Claude Code on most practical task types, based on our 8-task benchmark.

Can OpenCode work on large monorepos?

OpenCode works on large repos, but requires deliberate context scoping. On repos over 200 files, OpenCode tends to miss references in files outside its active context window — our repo-wide rename test introduced a stale import in an out-of-scope file. The workaround: pass explicit file paths or use a repo map (CLAUDE.md-equivalent) to prime the agent before complex multi-file tasks. Claude Code and Copilot agent mode handle large repo indexing more automatically, at the cost of higher token consumption.

Last updated: 2026-06-26