Check image file size, format, and dimensions online.
Drag & drop files here, or
Updated
File Size Checker on Synthixx Tools is a free browser-based utility: upload your file, configure options, run the job, and download the result with no account and no watermark. Check image file size.
File Size Checker runs entirely in your browser session against our secure API. There is no desktop install, no watermark on outputs, and no requirement to create an account for standard jobs. Keep reading for when to use this tool, practical tips, and honest limits.
Use File Size Checker when your goal matches the tool name and you want a free online workflow with clear privacy cleanup. Prefer related tools on this site if you need a different step in the same document pipeline.
Pick File Size Checker when the primary keyword intent matches your task. For multi-step pipelines (OCR → compress → protect), run each step with the matching tool rather than expecting a single upload to do everything. Related tools are linked at the bottom of this page.
For best results with File Size Checker: use clear filenames, stay within size limits listed in the upload UI, and preview pages when available before you run the job. Re-download promptly — outputs are temporary.
Stay within the upload limits shown in the tool UI. If a job fails, re-check file type and corruption (try Repair PDF). For password-protected inputs, unlock first. After success, download immediately and delete local copies you no longer need.
Synthixx Tools processes files for your requested job only. Transfers use HTTPS; completed job files are scheduled for automatic deletion. We do not sell your documents.
Privacy-first processing is a core product rule: uploads are used to fulfill the tool job you start, not for advertising profiles. Do not upload highly sensitive materials to any free online tool unless your threat model allows it — that advice applies industry-wide, including competitors. For account features (Design cloud sync), sign-in pages are noindexed; tool pages remain the public SEO surface.
After File Size Checker, continue with related PDF or image tools on Synthixx — merge, split, compress, convert, OCR, protect, and AI PDF Studio — all free and linked from this page.
Internal workflows that often follow File Size Checker include compress for email size, protect for sharing, OCR for searchable archives, and AI PDF Studio for summaries or Q&A. Browse the PDF Tools category hub for the full catalog. Image Resizer and Image Compressor cover bitmap workflows when your output is a picture rather than a PDF.
The report includes file size in bytes along with the detected format and image dimensions.
Files are processed securely and automatically deleted after your job completes.