Increase Image File Size Online
Increase an image's file size to a target KB or MB range while keeping the exact same pixel dimensions. Private, browser-based, no uploads.
Select images to increase file size
How to use
The whole flow runs in your browser — no account, no uploads.
- Upload your imagesDrop one or more files into the upload box, or browse your device.
- Set the target sizePick Size Range and enter a minimum and maximum, or Fixed Size Increase and enter a single target output size. Both start blank — nothing is pre-filled.
- IncreasePress Increase File Size — every file is encoded and measured locally.
- DownloadCheck each measured size and verdict, then save files individually or as a ZIP.
- Every step runs locally in your browser.
Key Features
Grow an image's actual file size into a target KB or MB range. Everything runs client-side: images are processed on your device and never uploaded.
- Exact dimensions keptEvery output is re-decoded and verified against the source's pixel size.
- Fixed encoder policyA bounded, fine-grained quality search is measured per file — no quality slider to guess with.
- Honest per-file verdictEach result says Target reached, Below range or Above range (Below/Above target in fixed mode), from the measured bytes.
- Nothing is uploadedEncoding runs in your browser; images never leave your device.
Frequently asked questions
No. The pixel dimensions are identical to the input — every output is re-decoded and verified before it is offered for download.
It re-encodes the image across a bounded, fine-grained quality range and measures every candidate byte for byte, aiming for the midpoint of your range (or for your single fixed target). JPEG and WebP grow with quality; PNG has no quality knob, so a PNG output walks a ladder of lossless encodings at the same dimensions (8- or 16-bit, compressed or uncompressed) and names the one used. When the best encoding still sits below your goal, JPEG and WebP use their own standards-compliant container space — a JPEG comment (COM) segment or an ignored WebP RIFF chunk — to reach that midpoint or fixed target without touching pixel data. The result says when that happened; it adds bytes, not quality or resolution.
No. A range below what the encoder can produce, one too narrow to express in the selected format, or a fixed size the format cannot represent may have no valid file that matches it. Container metadata closes gaps above the encoder's ceiling, but it is still measured, not assumed. Unreachable results are labelled Below range or Above range (Below target or Above target in fixed mode) with the closest valid output and the measured difference — the tool never fakes a number.
Yes. Upload several images, select them, and each is processed independently — one failure never blocks the others, and successful results download together as a ZIP.
No. The encoding policy is fixed so results stay predictable and visually faithful; only the target size is yours to set — a range to hit near its midpoint, or one fixed output size.
No. Everything runs locally in your browser; files never leave your device.