A free Kraken.io alternative that runs in your browser

Try it now: Image Compressor

Compress images instantly and reduce file size efficiently.

This is the real tool, not a demo. Open Image Compressor on its own page.

AltFTool vs Kraken.io

Kraken.io is an infrastructure product wearing a web interface. The free tier — 1 MB per image, 20 per batch, 100 MB of testing quota — exists to demo the API, not to be a daily tool, and resizing and conversion are deliberately PRO-only. If your goal is to optimise a site's images on a schedule, through S3 delivery or a WordPress plugin, that is what Kraken is for and this page will not change your mind. If your goal is to get one folder of images down in size today, a browser tool has no quota to run out of.

Kraken.io's free tier, in their own words

• Free account comes with a 100 MB testing quota, no credit card required
• The free Web Interface caps each image at 1 MB; the PRO interface raises this to 32 MB
• The free Web Interface allows up to 20 files per batch
• Image resizing and image conversion are PRO-only — the free interface optimises only
• Optimised images are available for download for 12 hours on the free Web Interface; Kraken's API docs state optimised images stay on their servers "for one hour only". PRO users keep files in Kraken.io Cloud Storage
• Paid plans are monthly data quotas — 500 MB (Micro) to 60 GB (Enterprise) — with overage billed at $5/GB down to $1/GB depending on plan

Paid pricing: Micro $5/month ($50/year), Basic $9/month ($90/year), Advanced $19/month ($190/year), Premium $39/month ($390/year), Enterprise $79/month ($790/year) — yearly billing includes 2 months free

Checked on 2026-07-25 against kraken.io/plans, kraken.io/web-interface, kraken.io/docs, kraken.io/, kraken.io/privacy. Vendors change their plans — if something here is out of date, trust Kraken.io's own page over ours.

What Kraken.io does better

Plenty of people should keep paying for Kraken.io, and these are the reasons why.

• The compression engine is the product, and it is a strong one: lossless and intelligent lossy modes tuned per format across JPG, PNG, WebP (incl. animated), GIF, SVG, AVIF, HEIC and PDF, with a detailed savings report.
• It is built for automation, not one-off use: a full REST API, WordPress plugin, Magento extension, and direct delivery of optimised files to S3, Azure, Cloud Files or SoftLayer. A browser-only tool cannot optimise an entire site's image pipeline on a schedule.
• Server-side processing means very large batches and heavy formats do not depend on the user's device or browser memory, and results are consistent regardless of the machine used.
• Kraken.io Cloud Storage keeps optimised assets retrievable for paid users, which suits agencies re-downloading assets long after the job ran.

And what AltFTool does not do

• No API, no WordPress or Magento plugin, no S3 delivery — nothing here can run on a schedule against a site's asset pipeline.
• Kraken's per-format tuning across animated GIF, SVG, AVIF and HEIC goes deeper than a browser re-encode does.
• No cloud storage of results. Kraken keeps optimised assets retrievable for paid users; we hand you the file and forget it.

Visit Kraken.io

Where each Kraken.io job goes here

Left: what you clicked on Kraken.io. Right: the tool that does the same job here.

• Optimise JPG / PNG / WebPImage Compressor
• Resize (PRO-only on Kraken)Image Resizer
• Convert format (PRO-only on Kraken)WebP to PNG / JPG Converter
• HEIC inputHEIC to JPG Converter
• Rasterise an SVGSVG to Image
• Compress a PDFPDF Compressor

The tools that cover Kraken.io work

• Image CompressorCompress images instantly and reduce file size efficiently.Open
• Image ResizerResize images with custom dimensions, social media presets, fit/crop modes, batch processing, and format export.Open
• WebP to PNG / JPG ConverterConvert WebP images to high-quality PNG, JPG, or PDF files quickly in your browser. Batch convert multiple files and download as a ZIP archive.Open
• HEIC to JPG ConverterConvert Apple HEIC/HEIF images into standard JPG or PNG files locally in your web browser. Supports batch conversions, custom image quality, and ZIP exports.Open
• SVG to ImageRasterise SVG markup to a downloadable PNG, JPEG or WebP at any scale, entirely in your browser.Open
• Image Quality CheckerAnalyze image quality with 10+ professional metrics including sharpness, brightness, contrast, noise, exposure, and histogram analysis.Open
• Image Metadata ViewerExtract and view complete image metadata including EXIF, IPTC, GPS, and file properties.Open
• PDF CompressorCompress PDF files to reduce file size while maintaining quality.Open

Questions people actually ask

Kraken's free web interface caps images at 1 MB. Does AltFTool?

No fixed cap. The practical limit is browser memory, which comfortably handles typical photographs — well past 1 MB. Kraken's cap protects a paid data quota; we have no quota.

Can I resize and convert for free?

Yes. Both are PRO features on Kraken's web interface; here they are separate free tools that run locally.

Should I still use Kraken?

If image optimisation is part of a deployment or CMS pipeline, yes. Their REST API, plugins and S3 delivery solve a problem a page in a browser cannot solve at all.