Open the workbook. Change it. Bring it back intact.
A real editable Grid sits in the exchange path: load source bytes, make a change, then export, re-import, and inspect the fidelity result beside the workbook. XLSX interchange guide →
Local engine: evaluated now. No new Excel or Google Sheets result is added; the on-demand evidence vault remains the source of truth.
XLOOKUP rate
Unavailable
PMT / month
Unavailable
NPV
Unavailable
IRR
Unavailable
STDEV.S
Unavailable
LET remaining payments
Unavailable
Schedule end
Unavailable
SEQUENCE output
Unavailable
Public change event: awaiting an analytical input edit.
Evidence vaultCompatibility test set and raw app resultsFilters, expected values, checksums, and explicit nonclaims
Compatibility results you can inspect
This page publishes a fixed, checked test set and the product's declared feature boundaries. It does not claim blanket Excel, Google Sheets, LibreOffice, or OpenFormula compatibility. Read the detailed checked results →
Local result100% — 2,290 of 2,290 supported tests passed locally
Test set version
1
Total tests
2,350
Formula tests
2,000
Edit sequences
250
Workbook tests
100
External app evidence is incomplete.0 reviewed results; 2,290 supported tests still lack a reviewed tested-app result. 60 unsupported tests are explicit nonclaims and are excluded from the local percentage.
Explicit result categories28 warning-behavior checks · 1 known difference · 0 reviewed regressions
Checked test set SHA-256bdf94c76df81ea1fa2e1bf96a557c41b21a0f11ea11ae612fcccc35157d7275a
Inspect representative checked tests
The compact page includes the first checked example for every function or feature, plus every available result state. Counts above always refer to the full 2,350-test set; the browser below contains 177 inspectable examples.
Local check passedTested app result missing
Test 1 of 2,350 · Shared spreadsheet behavior
add · Normal
Integer addition has the exact identity 1 + 1 = 2.
Input and expected result
Formula =1+1 at A1
No input cells are required.
Expected checked result
{
"type": "number",
"value": 2
}
Comparison tolerance
Exact type and value
Tested app results and differences
Missing results stay unavailable. A source description or expected value never substitutes for a reviewed app result.
Sheetwrite captured resultLocal check passed
Library version
0.3.0
Checked evidence
Test 1 in checked set v1
Result comparison
The local result matched the checked expected value under the published tolerance.
These product-level records cover import, export, preservation, warnings, and explicit unsupported behavior. They come from the existing checked inventory and link to exact sources; they do not turn missing Excel or Google Sheets results into claims.
Supported · Evaluated
Portable arithmetic, comparison, concatenation, and percent operators
Parses and evaluates +, -, *, /, ^, &, comparisons, unary signs, and postfix percent with deterministic coercion and errors.
Import
Formula source is preserved and evaluated when every token is in the portable subset.
Export
Canonical formula source is emitted to XLSX without cached-value fabrication.
Known boundary
This is a declared portable subset, not every Excel, Sheets, or OpenFormula coercion edge.
The workbench below exports this document to .xlsx bytes and re-imports them live; formulas, formats, the merge, and frozen rows survive.
toXlsxWorkbook / fromXlsxWorkbook on this page
Microsoft ExcelResult unavailable
Scope, limitations, and technical evidence
5 Excel-produced test files are listed from Apache POI commit 913c78891b, with expected file hashes and download sources. The workbook bytes and reviewed results are not checked in, so no Excel result is available here. Still unverified from Excel files: hidden worksheet, Sheetwrite metadata resave.
Metadata lists 1 Google Sheets-exported test file (google-sheets-public.xlsx) with its file hash recorded. The bytes and reviewed compatibility results are not checked in, so no Google Sheets result is available here. Still unverified from Google Sheets files: dates, merges, validations, notes, hidden active sheet, defined names, Sheetwrite metadata resave.
Operation evidenceStructured fidelity warning logThe latest import or round-trip, with public warning codes
Fidelity warnings, not silent loss
Every import and export reports what it could not preserve as structured XlsxWorkbookWarning records — coded, per sheet, per cell. Warning codes →
No interchange operation has run yet. Run the round-trip or import a fixture — warnings from that operation land here with their codes.
Delimited-text labCSV / TSV export, injection proof, and paste importLossy interchange is explicit and isolated from the workbook path
CSV and TSV, hardened
Delimited exports neutralize formula-injection payloads before a cell ever reaches a spreadsheet that would execute them.
Export the live document
Row OP-1045 stores =HYPERLINK("https://evil.example","Q3 total") as text — export the sheet and inspect what the CSV emits.
Delimited text is intentionally lossier: formulas leave as their computed values, and styles and merges do not exist in CSV/TSV at all.
Import pasted CSV
Security labHostile packages, aborts, and resource ceilingsFive hand-authored attack packages with typed rejection evidence
Resource limits and hostile input
Ceilings are enforced before anything allocates, and hand-authored hostile OPC/SpreadsheetML packages are rejected with typed errors. Resource limits →
byte ceiling
entry ceiling
dimension ceiling
compression-ratio ceiling
cell ceiling
AbortSignal honored
Hand-authored attack packages with recorded file hashes and the live verdict.
@sheetwrite/core ships no XLSX implementation — workbook interchange throws a typed error until a host registers a backend. This page loads @sheetwrite/xlsx/register lazily on the first XLSX action; CSV/TSV interchange needs no optional package at all.