Convert TIFF to PNG

TIFF to PNG starts with an explicit page

A PNG is one image. A TIFF may be a scanner bundle with dozens of top-level pages, plus auxiliary thumbnails or reduced-resolution subimages. The tool reads that structure before it converts anything. A single-page source presents its only page plainly; a multipage source requires a page radio selection. Auxiliary SubIFDs are reported but never promoted to pages or exported by accident.

The chosen page number is carried into the filename, such as archive-page-12.png. That rule avoids overwriting another extraction and makes the result traceable after it leaves the browser. Switching pages is immediate because the source inventory stays loaded. When the actual goal is to retain several scan pages in one file, TIFF to PDF is the multi-page destination.

What “lossless PNG” does and does not mean

PNG compresses the eight-bit working pixels without throwing any of them away. That makes it well suited to line art, screenshots, diagrams, text scans, palette images, and transparent artwork. It does not mean every TIFF property survives. A supported unsigned sixteen-bit grayscale source has more tonal values than this browser path writes, so those samples are scaled to eight bits and the reduction is named before the button and after the result.

The same distinction applies to an already lossy source. Some TIFF pages use compression that discarded detail when the file was created; wrapping the decoded result in PNG cannot recover it. The promise is precise: no additional lossy generation occurs after the supported page has become the verified eight-bit working raster.

Alpha survives only when TIFF actually defines it

TIFF's ExtraSamples tag distinguishes associated alpha, unassociated alpha, and unspecified extra channels. PNG needs straight alpha. The associated form is therefore unpremultiplied, the unassociated form is copied, and unspecified channels are rejected instead of guessed. That boundary protects both sides of the mistake: a converter must not discard real transparency, but it must not turn an unrelated data channel into invisible pixels either.

The reopened PNG is checked for actual alpha values and asymmetrical corner colors. A header saying RGBA is not enough. If transparency is important because the result will become a logo or overlay, this is the route that carries it; TIFF to JPG must flatten the same pixels onto a solid background.

Rotation and mirroring become real pixels

Orientation metadata can describe eight arrangements. Some swap width and height; some mirror the image along an axis. This converter applies the transform before encoding, and the output uses upright dimensions with no TIFF orientation dependency left behind. The verification samples different colors at different corners so the wrong mirror cannot pass merely because its dimensions match.

Page rows show both stored and oriented sizes in advance. That matters for scanned pages whose raw strip order is landscape even though every viewer presents them as portrait. Output is never stretched to make the numbers fit, and no resize control invents pixels in this conversion route.

The supported TIFF boundary is visible

Classic little- and big-endian TIFFs in the verified stripped, contiguous grayscale, RGB, palette, bilevel, compression, and bit-depth combinations are accepted. BigTIFF has a different directory layout and is rejected as BigTIFF. Tiled or JPEG-compressed pages, PlanarConfiguration 2, Predictor 3, signed or floating-point samples, CMYK, YCbCr, Lab, and unverified combinations are rejected by type rather than decoded approximately.

ICC profiles are not applied or embedded in the PNG. Geographic tags, EXIF, scanner-private fields, resolution metadata, and auxiliary imagery also stay in the source TIFF. The result is an sRGB-like viewing raster, not a color-managed publishing master or GeoTIFF. Keeping the original beside the PNG is essential whenever those properties carry meaning beyond the visible pixels.

Inspect the conversion receipt before saving

The receipt identifies the total page count, chosen page, source compression and samples, stored and upright dimensions, orientation transform, alpha handling, bit-depth conversion, profile/metadata boundary, output format, and byte count. Only after an independent decoder reopens the PNG and confirms its magic, dimensions, alpha, and pixel markers does the download become available.

TIFF bytes stay in the tab. A file picker, drop, or actual TIFF file from the clipboard reaches the same parser, with format determined from bytes rather than extension. Large material receives memory advice and cancelable progress, never an arbitrary upload limit — there is no upload path. The local-processing guide provides a practical way to check that claim.