Browser-native file tools with scoped local processing.

How ConvertUnlimited works

ConvertUnlimited is a browser-native utility site for common image, PDF, and developer tasks. For supported image workflows, the selected file is read by the browser, decoded with browser APIs such as Canvas, re-encoded in the selected output format, and offered back as a download from the same tab.

This local-processing model means ConvertUnlimited does not provide a server-side upload endpoint for supported image conversion flows. It does not mean every browser can process every file: very large images, unsupported formats, limited memory, or browser encoder differences can still affect results.

Conversion uses your computer's CPU and memory. Typical laptop workflows can handle moderate batches of phone-camera images, while hundreds of high-megapixel files can increase memory pressure and slow the browser tab. Start with roughly 50 images per batch and adjust based on device performance. See Tips for big batches for larger jobs.

Start with the tools index when you need a specific workflow, or read how local browser processing works before using the site with sensitive files.

Image format guide

Image formats differ by file size, quality behavior, transparency support, and compatibility. The notes below summarize the formats ConvertUnlimited reads and writes, and when each format is appropriate.

WebP

A modern image format developed by Google. At comparable visual quality, WebP files are often smaller than JPEG and PNG, and WebP supports transparency. Choose WebP for modern web delivery when the publishing system and target browsers support it.

JPEG

A broadly supported photo format. JPEG is lossy, does not support transparency, and remains compatible with most publishing systems, email clients, social platforms, printers, and older software. Choose JPEG when compatibility is the main requirement.

PNG

A lossless format with transparency support. PNG is suitable for screenshots, logos, icons, and graphics with sharp edges or solid-colour regions. The tradeoff is file size: photographic PNG files are often much larger than equivalent JPEG or WebP outputs.

GIF

A legacy bitmap format with basic animation support and a 256-colour palette. GIF can be inefficient for photos and complex graphics. ConvertUnlimited reads GIF files and converts the first frame; animated GIF output is not preserved.

SVG

A vector format based on XML drawing commands. ConvertUnlimited reads SVG files and rasterizes them at their natural dimensions. After rasterization, the output behaves like a pixel image, so convert SVG only when a raster output is required.

BMP

An uncompressed bitmap format. BMP files are usually large relative to their visual content. For web or sharing workflows, convert BMP to WebP, JPEG, or PNG unless the target system specifically requires BMP.

Choosing the right quality

The quality dropdown only applies to lossy formats (WebP and JPEG). PNG is lossless, so the dropdown is automatically disabled when PNG is selected. The four presets translate roughly to:

Original (1.0). Highest available encoder quality. Output may still differ from the source because the browser writes a new file.

High (0.9). High visual quality for photos and prominent web images, with moderate size reduction in many cases.

Recommended (0.75). Balanced web output for articles, product images, and social media assets.

Compact (0.5). Stronger compression for thumbnails, image grids, and bandwidth-constrained sharing. Text-heavy or high-contrast images may show artifacts sooner.

Tips for big batches

Use smaller batches when converting many large files:

Batch size. Start with about 50 images at a time. Larger batches may work, but browser memory allocation can briefly make the tab unresponsive.

RAM matters more than CPU. A 12-megapixel photo can require roughly 50 MB of memory after decoding. A batch of 100 such photos can temporarily require several gigabytes of memory. Closing other tabs can help on low-memory devices.

Mobile. Phones and tablets have less RAM and stricter background limits. Stick to smaller batches (10–20 images) on mobile devices.

ZIP downloads. After conversion, the "Download all as ZIP" button bundles outputs into one archive for easier batch download.

Frequently asked questions

Are there any limits?

There is no software-imposed file count limit. Practical limits depend on browser memory, CPU, source dimensions, and output format. Start with about 50 images per batch and increase only if the browser remains responsive.

Are my files uploaded to a server?

For supported image conversion flows, ConvertUnlimited does not provide a server-side upload endpoint. The browser reads and re-encodes selected image contents locally, then creates downloadable results in the tab. See how local processing works and how to verify it.

Will big batches slow my computer?

Briefly, yes. Each image decode and encode uses your CPU and RAM. Big batches (200+ high-resolution photos) can momentarily peak system memory. Use at your own discretion.

Why is it free?

What's the difference between WebP, JPEG, and PNG?

WebP is usually smaller at comparable visual quality and supports transparency. JPEG remains useful for broad photo compatibility. PNG is lossless and works well for screenshots, logos, icons, and transparent graphics. The full breakdown is in the image format guide.

Does converting reduce image quality?

Lossy formats such as WebP and JPEG discard information by design. At high quality settings, the difference is often difficult to see at normal display sizes. PNG is lossless, but re-encoding can still change file metadata and container details.

Can I convert HEIC, RAW, or PDF files?

Not currently. The browser canvas API only decodes image formats the browser natively supports. iPhone HEIC photos can be exported as JPEG from Photos.app and then converted here; PDFs need a dedicated PDF tool.

Why is my converted file sometimes bigger than the original?

This happens occasionally when you convert from a more efficient format (for example, WebP) to a less efficient one (for example, PNG), or when you ask for "Original" quality on an already-compressed source. The tool always shows the before / after sizes so you can decide whether the conversion was worth it.

What browsers are supported?

Current versions of Chrome, Edge, Firefox, Safari, and their mobile variants are supported. No browser extension or plugin is required.

Is there a desktop app?

No. ConvertUnlimited is a website. Supported workflows run through browser APIs without a separate desktop installation.

Privacy

Privacy build: This build removes ads, analytics, remote fonts, runtime CDN scripts, and file-operation telemetry. Selected files are processed in the browser using local JavaScript and browser APIs.

Selected images. ConvertUnlimited converts images entirely inside your browser. Selected file contents are processed locally in your browser for this supported workflow. ConvertUnlimited does not provide a server-side upload endpoint for this processing flow. File contents are not intentionally uploaded by this tool.

Contact. For privacy questions, reach out via the project's GitHub.