Documentlayer (formerly part of the Apilayer product family) offers a REST API for converting documents — Word, Excel, PowerPoint, HTML to PDF, and back. It's a clean, focused product. ChangeThisFile covers document conversion and much more: 690 routes including video, audio, ebook, archive, image, and font formats, with 161 routes that run entirely in the browser without uploading anything.
If documents are your only use case, both are worth comparing. If you need anything beyond documents, the choice is clear.
Quick verdict
For document-only conversions: Either can work. ChangeThisFile's free tier and zero-dependency integration give it an edge for new projects.
For multi-format workflows (images, video, audio, ebooks): ChangeThisFile. Documentlayer doesn't cover these categories.
For zero-dependency API integration: ChangeThisFile. Call /v1/convert directly with curl or any HTTP client — no library to install or maintain.
For privacy-sensitive documents: ChangeThisFile's client-side routes process HTML, Markdown, data files, and images in the browser. For server-side routes (DOCX, PDF), files are processed and deleted.
Pricing comparison
| Plan | ChangeThisFile | Documentlayer |
|---|---|---|
| Free tier | 1,000 conversions/month (no card) | Limited free requests (check documentlayer.com for current tier) |
| Entry paid | $29/mo — 10,000 conversions | Pay-per-use or monthly plans; see their site for current pricing |
| Mid tier | $99/mo — 50,000 conversions | Scales with volume |
| High volume | $499 Scale / $1,999 Growth | Enterprise available |
| Browser tool | Free, no signup, unlimited | Not available |
ChangeThisFile charges flat per conversion for all 690 routes. You're not billed more for a video conversion vs a document conversion — one call, one unit, regardless of format.
Feature comparison
| Feature | ChangeThisFile | Documentlayer |
|---|---|---|
| Free API tier | Yes — 1,000/mo, no card | Limited free tier |
| SDK required | No — curl/fetch/requests directly | API key auth, standard REST |
| Client-side conversions | Yes — 161 browser routes, zero upload | No |
| Conversion routes | 690 across all categories | Document-focused (Word, Excel, PPT, HTML, PDF) |
| Video / audio conversion | Yes | No |
| Ebook / archive / font | Yes | No |
| Webhooks | HMAC-signed, stdlib verifiable | Varies by plan |
| Idempotency keys | Yes | Not advertised |
| Browser conversion tool | Yes — free, no signup | No standalone tool |
Format and route coverage
Documentlayer's format list centers on Microsoft Office formats and PDF: DOC, DOCX, XLS, XLSX, PPT, PPTX, HTML to/from PDF, and related document conversions. It's a clean implementation of a specific use case.
ChangeThisFile's 690 routes span the same document formats plus images (JPG, PNG, WebP, HEIC, SVG, AVIF, GIF, BMP, ICO, TIFF, PSD), video (MP4, MKV, WebM, AVI, MOV, GIF), audio (MP3, WAV, FLAC, AAC, M4A), ebooks (EPUB, MOBI, AZW3), archives (ZIP, RAR, 7Z, TAR variants), fonts (TTF, OTF, WOFF, WOFF2), and data formats (CSV, JSON, YAML, TSV, XML, TOML). If your application ever needs to handle file formats beyond documents, ChangeThisFile scales with you on one API key and one endpoint.
Privacy and data handling
ChangeThisFile client-side routes run in the browser — files never leave the device for images, CSV/JSON/YAML, HTML, Markdown, and fonts. The architecture makes this a physical guarantee, not just a policy statement.
ChangeThisFile server-side routes upload over HTTPS, convert, return the result, and auto-delete. Async job files are retained in R2 for up to 24 hours, then deleted.
Documentlayer processes conversions server-side. They maintain a privacy policy, but all files traverse their infrastructure. For documents containing sensitive business data, consider whether server-side-only processing meets your requirements.
Developer experience: no SDK required
Documentlayer uses standard REST with API key auth. The integration pattern is familiar: attach your key, POST your file, receive output. ChangeThisFile uses the same pattern but goes a step further — we removed our SDKs entirely because they added maintenance overhead without adding value. The endpoint IS the SDK.
curl -X POST https://changethisfile.com/v1/convert \
-H "Authorization: Bearer ctf_sk_your_key" \
-F "file=@presentation.pptx" \
-F "target=pdf" \
--output presentation.pdf
No package manager, no version conflicts. If your runtime can make an HTTP POST, the integration is complete. Webhook verification is ~25 lines of HMAC using your language's standard library — no third-party crypto package needed.
Get a free key at changethisfile.com/v1/keys/free — no card required.
When to choose which
| Use case | Recommended |
|---|---|
| Free API tier, no card needed | ChangeThisFile |
| Zero-dependency integration | ChangeThisFile |
| Multi-category conversions (video, audio, ebook, image) | ChangeThisFile |
| Privacy-sensitive files | ChangeThisFile (client-side routes) |
| Standard document conversion (DOCX, XLSX, PPTX → PDF) | Either — both work well |
| Already integrated with Documentlayer, low conversion volume | Documentlayer (migration cost not worth it) |
If documents are all you convert, both services handle the core formats. The tie-breaker is the free tier and integration simplicity: ChangeThisFile's free API lets you test 1,000 conversions/month with no card and no client library to install. If your conversion needs grow beyond documents — images, video, audio, ebooks — you're already covered on the same key.