Iteration Layer vs SheetJS
SheetJS is everywhere — browser, Node.js, Deno — but the write-side API fights you at every step.
Why developers switch from SheetJS
SheetJS Community Edition has write limitations — and the Pro license gets expensive.
Declarative JSON, not low-level cell manipulation
SheetJS's write API requires building XLSX files from scratch — creating workbook objects, sheet objects, and cell objects manually. Styling requires the Pro edition. Our content model describes the entire sheet declaratively, with styles included.
No library to bundle or host
SheetJS is a library you bundle into your application or run in Node.js. We are a managed API: one HTTP call, no bundling, no version pinning, no binary size impact.
EU hosting with GDPR compliance
SheetJS runs wherever you run it. We process all spreadsheet generation on EU servers with zero data retention and a Data Processing Agreement available for every customer.
Feature-by-feature comparison
We went through the docs so you don't have to. Here's how every feature compares — including the ones where we're not the better choice.
| Feature | Iteration Layer | SheetJS |
|---|---|---|
| Formula support |
Yes
Generate spreadsheets with Excel-compatible formulas |
Limited
Formula support is limited in the free Community Edition — Pro required for full support |
| Multi-sheet support |
Yes
Generate workbooks with multiple named sheets |
Yes
Full multi-sheet workbook support |
| Output formats |
3 formats
XLSX, CSV, and Markdown output |
4+ formats
XLSX, CSV, HTML, and ODS output supported |
| Sheet definition style |
Declarative JSON
Entire spreadsheet described declaratively in a single JSON payload with styling included |
Low-level cells
Low-level cell object manipulation — styling requires the paid Pro edition |
| Free reading |
Generation only
API focused on spreadsheet generation, not reading existing files |
Built-in
Free Community Edition includes full spreadsheet reading and parsing capabilities |
| Browser-native |
Server-side
Server-side API requiring HTTP requests from the client |
Client-side
Runs entirely client-side in the browser without requiring a server |
| Legacy formats |
3 formats
XLSX, CSV, and Markdown — no legacy format support |
4+ formats
Supports legacy formats including XLS, ODS, CSV, and HTML tables |
| EU hosting |
EU only
All processing happens exclusively on EU-hosted servers |
Your choice
Runs on your infrastructure, so data residency depends on where you deploy |
| Pricing |
$0.033
1 credit per action |
License
Paid Pro for advanced writes |
| Infrastructure required |
None
Fully managed API with no bundling, hosting, or version management required |
Self-hosted
Library that must be bundled into your application or run in a Node.js process |
| GDPR / Data privacy |
Zero retention
No files or results stored beyond temporary 90-day logs |
Your responsibility
Data privacy depends entirely on your deployment and infrastructure choices |
Pricing
Start usage-based. Switch to a subscription when your volume becomes predictable.
Usage-based
Graduated pricing. Your effective rate decreases automatically as monthly usage grows.
- No monthly commitment
- Pay only for credits used
- Automatic volume discounts as usage grows
Predictable volume
Fixed recurring credit packs with lower effective credit prices for steady usage.
- Lower effective per-credit prices
- Fixed recurring credit packs
- Predictable monthly budget
Try Iteration Layer with 100 credits
Start with one shared trial pool before choosing subscription or pay-as-you-go billing.
Still evaluating?
See how we compare — and where the competition still wins. Choosing the right tool shouldn't require a week of research.
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100 trial credits included.