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Extract Text from Image (OCR)

Select an image containing text. The text will be extracted privately in your browser using WebAssembly. No data is sent to the cloud.

Complete Privacy

Extract text from scanned passports, invoices, legal documents, and receipts with absolute confidence. Your data never touches a remote server.

Local Neural Processing

Harness local processor cores to execute pattern recognition algorithms and neural layer compilations at high-performance WebAssembly speeds.

Copy and Export

Instantly capture characters, format text blocks into continuous scripts, copy elements to your clipboard, or save extracts directly to local files.

How Browser-Native OCR neural networks operate locally

Optical Character Recognition (OCR) was traditionally a complex, server-side workflow that required routing image files to cloud clusters or specialized desktop packages. This is because scanning pixels, mapping lines, isolating character grids, and executing machine-learning classifiers is highly memory-intensive.

Using modern WebAssembly sandboxing, DuckConvert runs a compiled C++ binary instance of the open-source Tesseract OCR engine directly inside your browser. Here is how it functions:

The 100% Client-Side OCR Workflow:

  1. Binarization & Filtering: The selected image is read into a canvas context. We convert the image to high-contrast monochrome (grayscale) to isolate text shapes clearly from backgrounds.
  2. Line and Word Segmentation: Tesseract crawls the monochrome pixels, analyzing spacing densities to identify paragraph borders, horizontal text line tables, and discrete word boxes.
  3. Neural Grid Matching: Isolated letter glyph paths are mapped against the downloaded and cached dictionary training weights to predict individual characters with high statistical confidence.
  4. Text Layout Compilation: Extracted strings are assembled into a formatted, selectable text box, ready for you to copy. Your documents remain completely secure.

Optical Character Recognition (OCR) FAQs

DuckConvert utilizes WebAssembly (WASM) and the open-source tesseract.js engine. When you select an image, the browser imports the OCR neural network directly into a local background thread (Web Worker). The network runs pattern recognition, analyzes pixel density matrices, detects font glyphs, and compiles individual characters into a selectable text layer. Everything runs locally in your device's memory.
Scanned documents often contain sensitive private details, including names, passport numbers, tax details, financial figures, or addresses. Traditional web-based OCR converters require sending these scans to cloud servers, where your data is logged, stored, and sometimes analyzed or harvested for AI training sets. DuckConvert runs 100% locally in your browser sandbox. No pixel or character data is ever transmitted to a server.
Yes. The first time you use our OCR tool, the browser downloads highly compressed language training models (roughly 5-10MB) directly from a CDN to identify fonts and words accurately. These weights are securely cached inside your browser's local CacheStorage. Once cached, the OCR tool can run completely offline, without needing any active internet connection.
We support standard image containers, including PNG, JPG, JPEG, WebP, and BMP. You can upload scanned pages, screenshots of code, receipts, text snippets, book photographs, or document snapshots to extract selectable text layers instantly.