--- title: Code interpreter description: Execute Python, JavaScript, and TypeScript code with rich output formats in Sandbox SDK. image: https://developers.cloudflare.com/dev-products-preview.png --- > Documentation Index > Fetch the complete documentation index at: https://developers.cloudflare.com/sandbox/llms.txt > Use this file to discover all available pages before exploring further. [Skip to content](#%5Ftop) # Code interpreter Execute Python, JavaScript, and TypeScript code with support for data visualizations, tables, and rich output formats. Contexts maintain state (variables, imports, functions) across executions. ## Methods ### `createCodeContext()` Create a persistent execution context for running code. TypeScript ``` const context = await sandbox.createCodeContext(options?: CreateContextOptions): Promise ``` **Parameters**: * `options` (optional): * `language` \- `"python" | "javascript" | "typescript"` (default: `"python"`) * `cwd` \- Working directory (default: `"/workspace"`) * `envVars` \- Environment variables * `timeout` \- Request timeout in milliseconds (default: 30000) **Returns**: `Promise` with `id`, `language`, `cwd`, `createdAt`, `lastUsed` * [ JavaScript ](#tab-panel-10536) * [ TypeScript ](#tab-panel-10537) JavaScript ``` const ctx = await sandbox.createCodeContext({ language: "python", envVars: { API_KEY: env.API_KEY },}); ``` TypeScript ``` const ctx = await sandbox.createCodeContext({ language: 'python', envVars: { API_KEY: env.API_KEY }}); ``` ### `runCode()` Execute code in a context and return the complete result. TypeScript ``` const result = await sandbox.runCode(code: string, options?: RunCodeOptions): Promise ``` **Parameters**: * `code` \- The code to execute (required) * `options` (optional): * `context` \- Context to run in (recommended - see below) * `language` \- `"python" | "javascript" | "typescript"` (default: `"python"`) * `timeout` \- Execution timeout in milliseconds (default: 60000) * `onStdout`, `onStderr`, `onResult`, `onError` \- Streaming callbacks **Returns**: `Promise` with: * `code` \- The executed code * `logs` \- `stdout` and `stderr` arrays * `results` \- Array of rich outputs (see [Rich Output Formats](#rich-output-formats)) * `error` \- Execution error if any * `executionCount` \- Execution counter **Recommended usage - create explicit context**: * [ JavaScript ](#tab-panel-10538) * [ TypeScript ](#tab-panel-10539) JavaScript ``` const ctx = await sandbox.createCodeContext({ language: "python" }); await sandbox.runCode("import math; radius = 5", { context: ctx });const result = await sandbox.runCode("math.pi * radius ** 2", { context: ctx }); console.log(result.results[0].text); // "78.53981633974483" ``` TypeScript ``` const ctx = await sandbox.createCodeContext({ language: 'python' }); await sandbox.runCode('import math; radius = 5', { context: ctx });const result = await sandbox.runCode('math.pi * radius ** 2', { context: ctx }); console.log(result.results[0].text); // "78.53981633974483" ``` Default context behavior If no `context` is provided, a default context is automatically created/reused for the specified `language`. While convenient for quick tests, **explicitly creating contexts is recommended** for production use to maintain predictable state. * [ JavaScript ](#tab-panel-10544) * [ TypeScript ](#tab-panel-10545) JavaScript ``` const result = await sandbox.runCode( `data = [1, 2, 3, 4, 5]print(f"Sum: {sum(data)}")sum(data)`, { language: "python" },); console.log(result.logs.stdout); // ["Sum: 15"]console.log(result.results[0].text); // "15" ``` TypeScript ``` const result = await sandbox.runCode(`data = [1, 2, 3, 4, 5]print(f"Sum: {sum(data)}")sum(data)`, { language: 'python' }); console.log(result.logs.stdout); // ["Sum: 15"]console.log(result.results[0].text); // "15" ``` **Error handling**: * [ JavaScript ](#tab-panel-10540) * [ TypeScript ](#tab-panel-10541) JavaScript ``` const result = await sandbox.runCode("x = 1 / 0", { language: "python" }); if (result.error) { console.error(result.error.name); // "ZeroDivisionError" console.error(result.error.value); // "division by zero" console.error(result.error.traceback); // Stack trace array} ``` TypeScript ``` const result = await sandbox.runCode('x = 1 / 0', { language: 'python' }); if (result.error) { console.error(result.error.name); // "ZeroDivisionError" console.error(result.error.value); // "division by zero" console.error(result.error.traceback); // Stack trace array} ``` **JavaScript and TypeScript features**: JavaScript and TypeScript code execution supports top-level `await` and persistent variables across executions within the same context. * [ JavaScript ](#tab-panel-10550) * [ TypeScript ](#tab-panel-10551) JavaScript ``` const ctx = await sandbox.createCodeContext({ language: "javascript" }); // Execution 1: Fetch data with top-level awaitawait sandbox.runCode( `const response = await fetch('https://api.example.com/data');const data = await response.json();`, { context: ctx },); // Execution 2: Use the data from previous executionconst result = await sandbox.runCode("console.log(data)", { context: ctx });console.log(result.logs.stdout); // Data persists across executions ``` TypeScript ``` const ctx = await sandbox.createCodeContext({ language: 'javascript' }); // Execution 1: Fetch data with top-level awaitawait sandbox.runCode(`const response = await fetch('https://api.example.com/data');const data = await response.json();`, { context: ctx }); // Execution 2: Use the data from previous executionconst result = await sandbox.runCode('console.log(data)', { context: ctx });console.log(result.logs.stdout); // Data persists across executions ``` Variables declared with `const`, `let`, or `var` persist across executions, enabling multi-step workflows: * [ JavaScript ](#tab-panel-10546) * [ TypeScript ](#tab-panel-10547) JavaScript ``` const ctx = await sandbox.createCodeContext({ language: "javascript" }); await sandbox.runCode("const x = 10", { context: ctx });await sandbox.runCode("let y = 20", { context: ctx });const result = await sandbox.runCode("x + y", { context: ctx }); console.log(result.results[0].text); // "30" ``` TypeScript ``` const ctx = await sandbox.createCodeContext({ language: 'javascript' }); await sandbox.runCode('const x = 10', { context: ctx });await sandbox.runCode('let y = 20', { context: ctx });const result = await sandbox.runCode('x + y', { context: ctx }); console.log(result.results[0].text); // "30" ``` ### `listCodeContexts()` List all active code execution contexts. TypeScript ``` const contexts = await sandbox.listCodeContexts(): Promise ``` * [ JavaScript ](#tab-panel-10542) * [ TypeScript ](#tab-panel-10543) JavaScript ``` const contexts = await sandbox.listCodeContexts();console.log(`Found ${contexts.length} contexts`); ``` TypeScript ``` const contexts = await sandbox.listCodeContexts();console.log(`Found ${contexts.length} contexts`); ``` ### `deleteCodeContext()` Delete a code execution context and free its resources. TypeScript ``` await sandbox.deleteCodeContext(contextId: string): Promise ``` * [ JavaScript ](#tab-panel-10548) * [ TypeScript ](#tab-panel-10549) JavaScript ``` const ctx = await sandbox.createCodeContext({ language: "python" });await sandbox.runCode('print("Hello")', { context: ctx });await sandbox.deleteCodeContext(ctx.id); ``` TypeScript ``` const ctx = await sandbox.createCodeContext({ language: 'python' });await sandbox.runCode('print("Hello")', { context: ctx });await sandbox.deleteCodeContext(ctx.id); ``` ## Rich Output Formats Results include: `text`, `html`, `png`, `jpeg`, `svg`, `latex`, `markdown`, `json`, `chart`, `data` **Charts (matplotlib)**: * [ JavaScript ](#tab-panel-10554) * [ TypeScript ](#tab-panel-10555) JavaScript ``` const result = await sandbox.runCode( `import matplotlib.pyplot as pltimport numpy as np x = np.linspace(0, 10, 100)plt.plot(x, np.sin(x))plt.show()`, { language: "python" },); if (result.results[0]?.png) { const imageBuffer = Buffer.from(result.results[0].png, "base64"); return new Response(imageBuffer, { headers: { "Content-Type": "image/png" }, });} ``` TypeScript ``` const result = await sandbox.runCode(`import matplotlib.pyplot as pltimport numpy as np x = np.linspace(0, 10, 100)plt.plot(x, np.sin(x))plt.show()`, { language: 'python' }); if (result.results[0]?.png) { const imageBuffer = Buffer.from(result.results[0].png, 'base64'); return new Response(imageBuffer, { headers: { 'Content-Type': 'image/png' } });} ``` **Tables (pandas)**: * [ JavaScript ](#tab-panel-10552) * [ TypeScript ](#tab-panel-10553) JavaScript ``` const result = await sandbox.runCode( `import pandas as pddf = pd.DataFrame({'Name': ['Alice', 'Bob'], 'Age': [25, 30]})df`, { language: "python" },); if (result.results[0]?.html) { return new Response(result.results[0].html, { headers: { "Content-Type": "text/html" }, });} ``` TypeScript ``` const result = await sandbox.runCode(`import pandas as pddf = pd.DataFrame({'Name': ['Alice', 'Bob'], 'Age': [25, 30]})df`, { language: 'python' }); if (result.results[0]?.html) { return new Response(result.results[0].html, { headers: { 'Content-Type': 'text/html' } });} ``` ## Related resources * [Build an AI Code Executor](https://developers.cloudflare.com/sandbox/tutorials/ai-code-executor/) \- Complete tutorial * [Commands API](https://developers.cloudflare.com/sandbox/api/commands/) \- Lower-level command execution * [Files API](https://developers.cloudflare.com/sandbox/api/files/) \- File operations ```json {"@context":"https://schema.org","@type":"TechArticle","@id":"https://developers.cloudflare.com/sandbox/api/interpreter/#page","headline":"Code interpreter ยท Cloudflare Sandbox SDK docs","description":"Execute Python, JavaScript, and TypeScript code with rich output formats in Sandbox SDK.","url":"https://developers.cloudflare.com/sandbox/api/interpreter/","inLanguage":"en","image":"https://developers.cloudflare.com/dev-products-preview.png","dateModified":"2026-04-21","publisher":{"@type":"Organization","name":"Cloudflare","url":"https://www.cloudflare.com/"},"isPartOf":{"@type":"WebSite","@id":"https://developers.cloudflare.com/#website","name":"Cloudflare Docs","url":"https://developers.cloudflare.com/"}} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"/directory/","name":"Directory"}},{"@type":"ListItem","position":2,"item":{"@id":"/sandbox/","name":"Sandbox SDK"}},{"@type":"ListItem","position":3,"item":{"@id":"/sandbox/api/","name":"API reference"}},{"@type":"ListItem","position":4,"item":{"@id":"/sandbox/api/interpreter/","name":"Code interpreter"}}]} ```