WASM Size Optimizer
Upload a WebAssembly (.wasm) file to strip debug sections, name tables, and build metadata — reduces deployable WASM size without affecting runtime functionality. Parses the binary format and shows every section with its size. Runs entirely in your browser with no signup required.
Upload a WebAssembly (.wasm) file to strip debug sections, name tables, and build metadata — reduces deployable WASM size without affecting runtime functionality. Runs entirely in your browser. Your WASM binary never leaves your device.
Drop your .wasm file here
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WebAssembly .wasm binary files are supported
Why Use Our WASM Size Optimizer?
Instant WASM Optimization
Upload any .wasm file and strip debug sections instantly in your browser — the tool parses the binary format, identifies strippable sections, and rebuilds the optimized binary in seconds.
Secure WASM Size Optimizer Online
Your WASM binary never leaves your device. All parsing and optimization runs locally in the browser sandbox — safe for proprietary or commercial WASM modules.
Section-Level Control
See every section in your WASM binary with its size — choose exactly which sections to strip with individual checkboxes and see the estimated saving before optimizing.
100% Free Forever
Optimize as many WASM files as you need, completely free. No account, no subscription, no file size limits, and no ads.
Common Use Cases for WASM Size Optimizer
Production Deployment Optimization
Strip debug sections before deploying WASM to production — reduces the binary size served to users and improves initial load time for WASM-heavy web applications.
Browser WASM Performance
Smaller WASM binaries parse and compile faster in the browser — stripping the name section alone can reduce parse time for large WASM modules by 10–30%.
CDN & Edge Delivery
Reduce WASM binary size before uploading to a CDN — smaller files reduce egress costs and improve cache hit rates for globally distributed WASM assets.
Serverless & Edge Functions
WASM modules deployed to Cloudflare Workers, Fastly Compute, or AWS Lambda have size limits — strip debug sections to stay within deployment size constraints.
Obfuscation & IP Protection
Stripping the name section removes function and local variable names from the binary — makes reverse engineering significantly harder for proprietary WASM modules.
CI/CD Build Pipeline
Add WASM optimization to your build pipeline — strip debug sections as a post-build step before packaging, ensuring production artifacts are always optimized.
Understanding WASM Binary Optimization
What is WASM Size Optimization?
WASM size optimization is the process of removing non-essential sections from a WebAssembly binary to reduce its file size for production deployment. WebAssembly binaries compiled with debug flags can contain large amounts of debug information — DWARF sections, function name tables, and build metadata — that are only needed during development. Our free WASM size optimizer parses the binary format, identifies strippable sections, and rebuilds the binary without them — entirely in your browser.
How Our WASM Size Optimizer Works
- Upload Your WASM File: Drag and drop or click to select any .wasm binary file from your device. The tool immediately parses the binary and shows all sections with their sizes.
- Select Sections to Strip: Strippable sections are pre-selected automatically. Review the section table and deselect any sections you want to keep. The estimated saving updates in real time.
- Download Optimized Binary:Click "Optimize WASM" — the tool rebuilds the binary without the selected sections and downloads it automatically.
What Gets Stripped
- Name Section: Function and local variable names used by browser DevTools — not needed at runtime, safe to strip for production.
- DWARF Debug Sections: .debug_info, .debug_line, .debug_str, and related sections — can be larger than the code itself in debug builds.
- Producers Section: Build tool metadata (compiler name, version, SDK) — not needed at runtime.
- sourceMappingURL: Source map URL embedded in the binary — only needed for browser DevTools debugging.
What Is Always Preserved
All sections required for runtime execution are preserved: Type (function signatures), Import (external imports), Function (function index table), Table (indirect call tables), Memory (memory definitions), Global (global variables), Export (exported functions and memory), Start (entry point), Element (table initializers), Code (function bodies), and Data (memory initializers). The optimized binary is functionally identical to the original.
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Frequently Asked Questions About WASM Size Optimizer
A WASM size optimizer strips non-essential sections from a WebAssembly binary — such as debug information, function name tables, and build metadata — to reduce the file size for production deployment. Our free online WASM size optimizer runs entirely in your browser — no signup or server upload required.
No. The tool only strips sections that are not required for runtime execution. The name section (function/local names), DWARF debug sections, producers metadata, and sourceMappingURL are all documentation/debug-only sections. All code, imports, exports, memory, tables, and data sections are preserved exactly.
Yes, complete privacy is guaranteed. All parsing and optimization runs entirely client-side in your browser. Your WASM binary — which may contain proprietary algorithms or commercial code — never leaves your device and is never uploaded to any server.
Yes. The WASM size optimizer is 100% free with no signup, no subscription, no file size limits, and no ads. You can optimize as many WASM files as you need.
The name section is a custom section that stores human-readable names for functions, locals, and other WASM entities. It is used by browser DevTools to show readable function names in stack traces and profilers. It has no effect on runtime behavior and is safe to strip for production deployments.
DWARF debug sections (.debug_info, .debug_line, .debug_str, etc.) are embedded debugging information generated by compilers like Emscripten and wasm-pack. They allow native debuggers to map WASM instructions back to original source code. They can be very large (often larger than the code itself) and are not needed for production deployment.
It depends on how the WASM was compiled. Debug builds with DWARF sections can be 3–10× larger than the optimized version — stripping debug sections can reduce size by 60–80%. Release builds with only the name section typically achieve 5–20% reduction. The section table shows the exact size of each strippable section before you optimize.
Similar, but browser-based. wasm-strip (from the WebAssembly Binary Toolkit) and wasm-opt (from Binaryen) are command-line tools that perform the same section stripping. Our tool provides the same functionality in your browser without requiring any installation. For advanced optimizations like code rewriting and dead code elimination, wasm-opt provides additional capabilities beyond section stripping.