Spreadsheet rendering SDK · self-hosted
The spreadsheet goes in.
The truth comes out.
Rendlio renders Microsoft Excel workbooks exactly as they print—on your servers, no Office, no LibreOffice—and signs every conversion with a machine-readable compatibility report. What cannot be rendered faithfully is reported explicitly. Nothing is silently approximated.
$ dotnet tool install -g Rendlio.Tool Scored against Microsoft Excel print output, page by page
Machine-readable JSON—honest by contract
CLI, Docker, NuGet—no data ever leaves
Unlimited developers, SaaS and OEM included
First faithful PDF in five minutes.
No Office install, no service account, no meeting. One self-contained binary—or the container, if that is your shape.
$ dotnet tool install -g Rendlio.Tool
$ rendlio convert invoice.xlsx -o invoice.pdf --pdfa --report r.json
parse → layout → render → verify · 1.8s
✓ invoice.pdf PDF/A-2b · 3 pages · deterministic
✓ r.json 214/214 supported · 0 warnings
# Containerised? Same bytes out.
$ docker run ghcr.io/rendlio/rendlio convert invoice.xlsx -o invoice.pdf - 01
Install the tool
One .NET global tool or one container image. Self-contained; nothing else to provision.
- 02
Convert with a report
--report r.jsonemits the compatibility report—every feature found in the workbook and exactly how it was rendered. - 03
Gate on honesty
Wire the report into CI. If a workbook contains an element that cannot be rendered faithfully, the exit code tells you first.
Every format has limits.
None are hidden.
Some workbook features have no faithful equivalent in a static document. Rendlio's report names every feature and states, with a code, exactly how it was handled. Green is a guarantee, not a hope.
| Feature | Status | Code | Detail |
|---|---|---|---|
| Number formats41 distinct formats, including accounting and custom | SUPPORTED | — | Rendered to Excel display strings with locale pinned. |
| Conditional formatting3 rules using cached values | SUPPORTED | — | Data bars and colour scales painted from cached evaluation. |
| SmartArt diagramsOrg chart and process diagram | SUPPORTED | — | Shapes, connectors, labels, and theme styling rendered faithfully. |
| Interactive slicer controlsPivotTable filter, sheet “Dashboard” | PARTIAL | W5104 | Current selection rendered; live filtering has no static PDF equivalent. |
| External workbook links2 references | SKIPPED | W1011 | Cached values rendered; live refresh would require network access. |
| Legacy VML 3-D extrusionDecorative effect on archived worksheet | UNSUPPORTED | W6208 | Obsolete decorative effect omitted; worksheet content is unaffected. |
When faithful rendering is technically impossible, you will know before your customer does.
Same workbook in,
same bytes out.
No clock
Engine code contains no clock, no randomness, and no network—enforced by Roslyn analyzers in CI.
Reproducible
Byte-identical PDF/A across operating systems and architectures. Archive a hash today and regenerate it later.
Verifiable
Signed releases, an SBOM, and veraPDF validation in CI provide evidence procurement teams can verify.
Built for production.
Ready for procurement.
Built and sold by the Rendlio Association (Verein Rendlio), a Swiss non-profit. Product terms, source access, and enterprise support remain commercial-grade.
Source-available, BUSL-1.1
Audit the parser that touches your files. Every version becomes Apache-2.0 after four years.
No phone-home. Ever.
Offline licence files, ES256-signed. The analyzers that forbid network calls run on every commit.
Escrow & provenance
Source escrow for Enterprise, signed releases, and an SBOM per build—procurement questionnaires welcome.
Public fidelity corpus
Acceptance scores are published and reproducible. We show the corpus, not adjectives.
No seat counting.
No server counting. No sales call.
Free in production for companies under $1M revenue. Above it: one price, everything included—unlimited developers, SaaS, and OEM redistribution built in.
$1,499
- Unlimited developers, unlimited servers
- SaaS and OEM included—no redistribution tax
- Perpetual fallback—the version you have works forever
- Renew updates at 40% when you choose
$3,999
- Everything in Professional, group-wide
- Source escrow and signed attestations
- Priority support and compatibility triage
- Invoice / PO purchasing
30-day trial. Full engine.
Evaluate spreadsheet rendering, compatibility reports, and PDF/A output on your own infrastructure.