Uploadcare and ChangeThisFile both deal with files and APIs, but they're built for different jobs. Uploadcare provides a JavaScript upload widget, CDN hosting, and URL-based image transformations — it's infrastructure for apps that accept user file uploads. ChangeThisFile is a converter: you send a file, specify a target format, and get the converted file back.
This comparison is for developers who've encountered both and want to understand which fits their specific use case — or why they might need neither, one, or both.
Quick verdict
For apps that accept user uploads (profile photos, documents, media): Uploadcare. Upload widget, CDN hosting, and delivery are its core strengths.
For converting files between formats programmatically: ChangeThisFile. One POST endpoint, 690 routes, free tier with no card.
For developers who want the simplest possible API: ChangeThisFile wins clearly — no upload widget to configure, just a POST with a file and a target format. Source is auto-detected from the filename.
For image optimization and CDN delivery: Uploadcare's CDN transformations are well-suited; ChangeThisFile doesn't host or serve files.
Pricing comparison
Competitor pricing below is as of April 2026 - check the vendor's current pricing page before deciding.
| Plan | ChangeThisFile | Uploadcare |
|---|---|---|
| Free tier | 1,000 conversions/month (no card) | 3,000 uploads/mo, 1GB bandwidth |
| Entry paid | $29/mo — 10,000 conversions | $39/mo — 10,000 uploads, 10GB |
| Mid tier | $99/mo — 50,000 conversions | $99/mo — 50,000 uploads, 50GB |
| High volume | $499/$1,999/mo | $299+/mo or enterprise |
| Pricing model | Per conversion (flat count) | Per upload + bandwidth GB |
| CDN hosting | No (converts and returns file) | Yes (files hosted on Uploadcare CDN) |
Uploadcare's pricing bundles uploads and bandwidth — your files live on their CDN, so you pay for storage and delivery over time. ChangeThisFile has no hosting; you get the converted file back in the response and store it yourself. For one-off or batch conversions where you own your storage, ChangeThisFile is more cost-efficient.
Feature comparison
| Feature | ChangeThisFile | Uploadcare |
|---|---|---|
| Free API tier | Yes — 1,000/mo, no card | Yes — 3,000 uploads/mo |
| SDK required | No — curl/fetch/requests directly | Optional JS widget (recommended) |
| Image conversion | Yes — 690 routes incl. HEIC, AVIF, PSD | Yes — URL-parameter transforms |
| Video conversion | Yes (MP4, WebM, MKV, AVI, MOV) | Limited (video processing add-on) |
| Document conversion | Yes (PDF, DOCX, XLSX, EPUB, etc.) | No (upload and serve only) |
| CDN hosting | No | Yes |
| Upload widget (JS) | No | Yes — drag-and-drop UI component |
| Client-side conversions | Yes — 161 routes run in browser | No |
| Webhooks | Yes (HMAC-signed) | Yes |
| Async jobs | Yes (files >100MB) | Yes |
Format and conversion coverage
Uploadcare focuses on image formats: JPEG, PNG, WebP, AVIF, GIF, BMP, TIFF, and a few others. Its image CDN applies transformations (resize, crop, format conversion, compression) via URL parameters. Non-image file types can be uploaded and hosted but not transformed — Uploadcare stores and delivers them as-is.
ChangeThisFile covers 690 specific conversion routes across 9 categories. Image formats include everything Uploadcare handles plus HEIC, PSD, SVG, ICO, and more. Beyond images: video (MP4, WebM, MKV, AVI, MOV, 3GP, FLV), audio (MP3, WAV, FLAC, AAC, M4A, OGG), documents (PDF, DOCX, ODT, RTF, HTML, Markdown), data (CSV, JSON, YAML, XML, TOML), spreadsheets (XLSX, XLS), fonts (TTF, OTF, WOFF, WOFF2), ebooks (EPUB, MOBI, AZW3), and archives (ZIP, RAR, 7Z, TAR). For anything outside image hosting, ChangeThisFile has significantly broader coverage.
API and developer experience
ChangeThisFile API is designed to need no SDK. One endpoint, one POST, source auto-detected from filename:
curl -X POST https://changethisfile.com/v1/convert \
-H "Authorization: Bearer ctf_sk_your_key" \
-F "file=@document.docx" \
-F "target=pdf" \
--output result.pdf
Get a free key at changethisfile.com/v1/keys/free. No job polling for normal files, synchronous response.
Uploadcare provides a JavaScript upload widget for browser-side uploads and a REST API for server-side operations. The widget handles drag-and-drop, progress UI, file validation, and direct-to-CDN uploads. For developers building apps where users upload files, this is genuinely useful. For back-end batch conversion pipelines, it's more infrastructure than you need.
Uploadcare also supports URL transformations for images it hosts — similar to imgix, you can append operations like -/resize/300x/ to image URLs. These are processed on delivery, not as separate API calls.
When to choose which
| Use case | Recommended |
|---|---|
| User file upload widget for a web app | Uploadcare |
| Host and serve user-uploaded images from a CDN | Uploadcare |
| Convert HEIC, PSD, AVIF, or other image formats | ChangeThisFile |
| Convert video, audio, documents, or archives | ChangeThisFile |
| Simple API without installing a library | ChangeThisFile |
| Free tier with no credit card | Both (different free limits) |
| Privacy-sensitive files — no server upload | ChangeThisFile (client-side routes) |
| Image resize/crop on delivery via URL params | Uploadcare |
If your use case is accepting user file uploads in a web app and serving them from a CDN, Uploadcare is designed for exactly that. If you need to convert files between formats — especially video, audio, documents, or ebooks — ChangeThisFile's free API tier is a better fit — 690 routes, call /v1/convert with curl or fetch.