Data Trimmer

WHAT IT DOES

Data Trimmer is a browser extension that cleans and filters tabular data directly on any webpage. It detects tables and lets you select a column to trim, filter, or remove unwanted data. You can remove rows that contain values outside a specified numeric range, eliminate statistical outliers (values beyond two standard deviations), strip blank rows, trim excess whitespace, or delete cells that contain non-numeric text. The tool applies changes directly to the table's DOM, giving you immediate visual feedback. Every operation includes a full undo capability, so you can experiment with different trim settings without fear of losing original data. This is ideal for data analysts, researchers, and anyone working with messy tables who needs to quickly prepare clean datasets for analysis or visualization.

WHERE IT RUNS

Data Trimmer works on any website that presents data in HTML tables. It runs locally in your browser as a lightweight userscript, detecting table structures across the web. It works on financial spreadsheets, scientific datasets, inventory systems, survey results, sports statistics, e-commerce product tables, research databases, and internal business tools. The tool handles static tables, dynamically updated tables, and tables inside iframes where permitted. All data processing occurs entirely in your browser—no information is ever sent to any server, and your original data remains intact until you choose to apply changes.

HOW TO USE

After installation, open the floating panel by clicking the extension icon. The panel automatically scans the current page and lists every table found. Select a table from the dropdown, then choose a column to clean. The tool highlights numeric columns for easy identification. Choose a trim method from four options: remove values outside a user-defined range, remove statistical outliers beyond two standard deviations, remove values below a threshold, or remove values above a threshold. Set minimum and maximum thresholds using the input fields. Additional options let you remove empty rows, trim whitespace from cell contents, and remove cells that contain non-numeric text. Click the Trim Data button to apply the cleaning operation. The table updates immediately, and a status message shows how many rows were removed. If you are not satisfied with the result, click Undo to revert to the original table data instantly.

REAL MECHANISM — WHY THIS WORKS

Most data cleaning tools rely on treating table content as a flat text stream and applying regular expressions, which fails when tables contain merged cells, complex nested structures, or inconsistent formatting. Data Trimmer uses a different approach: it first constructs a logical grid representation of each table by traversing the DOM and mapping each cell to its row and column position while resolving rowspan and colspan attributes. Once the grid is built, the tool performs a type inference pass that examines cell content through a multi-stage pipeline. The first stage extracts raw text while preserving whitespace and special characters. The second stage applies locale-aware number parsing that handles comma and dot decimal separators, thousand separators, and negative signs. The third stage validates candidate numbers against pattern filters that distinguish true numeric values from phone numbers, postal codes, dates, and product identifiers. When a trim operation is triggered, the tool applies the selected filter criteria across the normalized grid, building a list of rows to remove. Instead of deleting rows individually, the tool uses a reverse-index deletion strategy—removing rows from the bottom up to preserve index integrity and avoid shifting issues. Every operation is wrapped in a transaction that stores the complete table state before modification, enabling instant, complete undo with a single DOM restore operation. This transaction model ensures that even complex multi-step operations can be reverted reliably.

THE PANEL

The floating panel is fully draggable and remembers its position per site, snapping to the edges of the viewport when dragged near them. You can collapse the panel to a small icon to minimize screen distraction and expand it back with a single click. The panel is resizable from the bottom-right corner, giving you more space to view options and controls. Press the Escape key to close the panel instantly. The panel remains open across page navigation within the same domain, maintaining your current selections and trim settings. All preferences—selected table, selected column, trim method, thresholds, and toggle states—are saved per domain for a seamless experience.

PLEASE NOTE

Data Trimmer requires the free BotGentz extension to be installed and enabled, as it relies on the cross-extension messaging API provided by BotGentz for table detection and DOM access permissions. Because websites frequently update their structure, table detection and cleaning operations may require periodic script updates to maintain compatibility. If a table is not detected correctly or a trim operation does not behave as expected, please check for updates or report the issue. All data processing occurs entirely in your browser. No table data, cleaning operations, or analysis results are ever sent to any server. The extension does not read, store, or transmit any personal information. It only reads and modifies the DOM of the pages you choose to interact with, and every modification is fully reversible using the Undo function.