Spreadsheet Editor is the site's workbook editor, and it runs in your browser tab. It looks and behaves like the spreadsheet you use at work: a ribbon with Home, Insert, Page Layout, Formulas, Data, Review and View tabs, a formula bar and name box, sheet tabs along the bottom, a fill handle, frozen panes and the familiar keyboard shortcuts. XLSX is its native format, so a workbook from Excel, LibreOffice or Google Sheets opens with its formulas, styles, tables and charts, and saves back the same way. CSV and TSV files open and save too.
The editor is delivered by this site and executed by your browser, so your numbers never leave your computer. There is no account, no upload and no limit on how often you use it. The first visit downloads about 7 MB, which the browser keeps cached; later visits start in a moment.
What this spreadsheet editor can do
The calculation engine supports more than five hundred worksheet functions, from SUM and VLOOKUP to XLOOKUP, SUMIFS, TEXTJOIN, LET and LAMBDA, with dynamic arrays that spill results into neighbouring cells. Formulas are entered in point mode with coloured references, and structured references work on tables. Cells take the full number-format language (currency, accounting, dates, percentages, custom codes), fonts, fills, borders, alignment and merged ranges; Format as Table adds banded rows, a header with filter buttons and a totals row. Conditional formatting covers highlight rules, colour scales, data bars and icon sets, and data validation restricts what a cell accepts.
The Data tab sorts and filters ranges, adds subtotals and outlines, and fills a pattern with Flash Fill. The Insert tab adds charts in seventeen types (column, bar, line, pie, scatter, area and more) with a Chart Design tab and a format pane, sparklines inside cells, pivot tables with a field list and report filters, pictures, shapes, comments and hyperlinks. Page Layout sets the print area, margins and page breaks, and the workbook can be exported to PDF. Find and replace, undo across many steps and a copy-on-write engine that keeps large workbooks responsive round out the everyday toolset. The File page starts from a blank workbook or one of the sample workbooks (a household budget, a sales dashboard, a gradebook) to see what is possible.
When to use a spreadsheet editor in the browser
Checking a workbook on a machine without Excel
Someone sends an XLSX with the quarter's figures and you are on a laptop with no office suite. Open it here, read the formulas, fix the one that points at the wrong row, add a chart and save the workbook back without installing anything.
Cleaning up a CSV export
An export from a shop system or a bank arrives as CSV. Open it, sort by date, filter the rows you need, add a column with a formula, format the amounts as currency and save it as XLSX, or back to CSV for the next tool in the chain.
Working on figures that must stay private
Payroll, budgets, patient lists and client data should not be pasted into an online spreadsheet that stores them on someone else's server. Because the whole application runs in your browser, nothing is transmitted, and the editor keeps working offline once its files are cached.
How the editor runs in your browser
The editor is a complete spreadsheet engine compiled to WebAssembly: the parser, the dependency graph that recalculates only the cells that changed, the chart renderer and the XLSX reader and writer all run inside the page. The grid is virtualised, so only the cells on screen are laid out, and the interface is drawn on the graphics card through WebGPU where the browser offers it and WebGL2 otherwise. That is why a current desktop browser is required; the frame is served by this site and no third-party host is involved.
Opening a workbook reads it through the browser's file picker (or a drop onto the grid) into memory, and Save triggers a normal browser download. An XLSX saved here keeps its styles, themes, formulas, tables, conditional formats, validation, comments, hyperlinks, charts, pictures, sparklines, pivot tables and print settings, so it opens in Excel as you left it. Older XLS workbooks open with their values, formulas and number formats.
Como usar esta ferramenta
- Wait for the editor to load. The first visit downloads about 7 MB; afterwards it starts from the browser cache.
- Pick Blank workbook or a sample on the start dialog, or click Open and choose an XLSX, XLS, CSV or TSV file. Click into the grid once so keyboard shortcuts reach the editor.
- Enter data and formulas, format cells, sort and filter, and add tables, charts or a pivot table from the ribbon. The Fullscreen button above the frame gives the grid more room.
- Save the workbook with the save button or Ctrl+S; it downloads as XLSX. Use File > Export for CSV or PDF.
Limitations
- A desktop browser with WebGL2 or WebGPU is required. Phones show a notice instead of the editor; tablets can open it, but the grid expects a keyboard and a mouse.
- The first load is about 7 MB. Later visits use the browser cache.
- This is a capable editor for everyday work, not a complete substitute for a desktop spreadsheet. Macros and VBA do not run, some chart options are missing, and a workbook that relies on add-ins or external data connections will not refresh them.
- Very large workbooks with hundreds of thousands of formulas can be slow, because recalculation runs on a single thread in the browser.
- There is no save to disk without your action. Save before closing or reloading the tab, because the workbook lives only in the tab's memory.