12 languages. Stateful sessions. gVisor isolation. MCP-native. Build agents that iteratively debug code, online judges that grade in milliseconds, or coding platforms that scale.
Every other code-execution API stops at "send code, get output." We ship the full toolkit AI agents and modern developer tooling actually need.
Persistent sandboxes that retain variables, files, and installed packages across calls. Build code interpreters that actually feel like REPLs.
# Variables persist → POST "x = 42" → POST "print(x*2)" → stdout: "84"
pip, npm, gem, cargo — all inside the session, all sandboxed. Top-1k packages cached for sub-3-second installs.
# pandas in < 3s manager: "pip" packages: ["pandas", "numpy"]
Server-Sent Events deliver live stdout/stderr as code runs. No polling, no buffering. Render to a terminal in real time.
# SSE events → stdout: "Step 1" → stdout: "Step 2" → result: exit 0
Submit a long-running job, walk away. We deliver a signed callback to your URL when it finishes. HMAC-SHA256 verification built in.
# Fire-and-forget async: true callback_url: "…/hook" # HMAC-SHA256 signed
Python 3.12, Node 22, TypeScript 5.4, Go 1.22, Java 21, GCC 14, Bash 5.2, Rust 1.85, Ruby 3.3, PHP 8.4, .NET 9. Latest stable, not stale 2018 runtimes.
# All current "rust" // 1.85 "ruby" // 3.3 "php" // 8.4 "csharp" // .NET 9
User-space kernel intercepts every syscall before it reaches the host. Strictly stronger than container-only sandboxes. Built for hostile input from day one.
# Isolation stack code → Docker → gVisor (runsc) → host kernel
Latest stable versions. Pre-warmed pools. Strict resource limits. Each running in its own isolated gVisor sandbox.
Same API, four execution patterns. Pick the one that matches your workflow.
curl -X POST .../v1/execute \ -H "X-RapidAPI-Key: $KEY" \ -d '{"language":"python3","code":"print(2+2)"}'
curl -N -X POST .../v1/execute/stream \ -H "X-RapidAPI-Key: $KEY" \ -d '{"language":"python3","code":"..."}'
curl -X POST ".../v1/execute?async=true" \ -H "X-RapidAPI-Key: $KEY" \ -d '{"code":"...","callback_url":"https://your.app/hook"}'
curl -X POST .../v1/sessions/$SID/execute \ -H "X-RapidAPI-Key: $KEY" \ -d '{"code":"x += 1; print(x)"}'
SandboxAPI is available as an MCP server with 11 tools — execute_code, sessions, batch, async, package install, and more.
Paste this into your MCP-compatible AI assistant. Done. Your AI can now run code in 12 languages, install packages, and keep state across calls.
{
"mcpServers": {
"sandboxapi": {
"url": "https://mcp.sandboxapi.dev/mcp",
"headers": {
"Authorization": "Bearer YOUR_API_KEY"
}
}
}
}
Field-level mapping, honest comparison, and recommendations by persona.
Real-world examples you can run right now. Click any example to try it in the playground.
Run AI-generated functions against a test harness, get structured pass/fail results
Try it →Stateful sessions and package install for a debugging agent that retries on errors and learns from compile failures
See pattern →Run generated business rules to validate records with detailed error reporting
Try it →Submit a ZIP with custom compile and run scripts. Set expected_output, get an automatic wrong_answer status
See it →Benchmark solutions at scale and verify time complexity meets O(n) requirement
Try it →Run the same challenge across 12 languages and verify output consistency
Try it →Score student code against a weighted rubric with 14 test cases across 3 categories
Try it →Validate student functions against hidden test suites with detailed feedback
Try it →Test student expressions with stdin input and automated evaluation
Try it →Check production configs against security rules, flag errors and warnings
Try it →Transform raw sales data into formatted reports with leaderboards and breakdowns
Try it →Run ETL pipeline steps and validate each transformation produces correct output
Try it →All plans include 12 languages, gVisor isolation, multi-file programs, output verification, and streaming. Sessions, package install, and async unlock at Pro and above.
Get your API key and start executing code in minutes. 500 free executions, no credit card required.