Format reference
What each format is, what it's good at, and what it isn't. Use this as a cheat sheet when you're picking a target format.
PDF — Portable Document Format
The default for finalized documents. PDF locks layout, fonts, and pagination so the file looks identical on every device. Good for résumés, contracts, invoices, reports, and anything you're sending out for review or print. Bad for editing — PDFs aren't structured documents, so editing usually means converting to DOCX first. Need to lift a page out as an image instead? PDF → JPG and PDF → PNG rasterize the pages — single-page in, single image out; multi-page in, ZIP of one image per page out. Too big to email? Shrink large PDFs with our PDF compressor — typically 50-80% smaller with no visible quality loss.
MIME: application/pdf · Extension: .pdf · Best target for: finalizing, sending, printing.
DOCX — Microsoft Word
The standard word-processing format since 2007. Editable in Word, Google Docs, LibreOffice, Pages, and basically every other word processor. Carries fonts, headings, tables, images, and tracked changes. Use it for documents you'll keep editing; switch to PDF when you're done.
MIME: application/vnd.openxmlformats-officedocument.wordprocessingml.document · Extension: .docx · Best target for: editing.
XLSX — Microsoft Excel
The standard spreadsheet format since 2007. Editable in Excel, Google Sheets, LibreOffice Calc, Apple Numbers. Carries formulas, charts, multiple sheets, merged cells, conditional formatting, and cell colors. Convert XLSX to CSV to extract the first sheet as plain rows for scripts and databases, or XLSX to PDF to lock the layout for review and print.
MIME: application/vnd.openxmlformats-officedocument.spreadsheetml.sheet · Extension: .xlsx · Best target for: editing, formulas, multi-sheet workbooks.
CSV — Comma-Separated Values
Plain-text tabular data, one row per line. The lingua franca of scripts, databases, BI tools, and data pipelines. No formulas, no formatting, no multiple sheets — just values. Convert CSV to XLSX to hand a script's output to a colleague who lives in Excel, or CSV to PDF for a printable table without round-tripping through a spreadsheet app.
MIME: text/csv · Extension: .csv · Best target for: scripting, bulk data import, version control.
TXT — Plain text
Just characters, no formatting. Useful when you want the words and nothing else — for grep, copy-paste into a code editor, feeding into a script, or stripping every trace of layout from a document. Pair with OCR to pull text out of an image.
MIME: text/plain · Extension: .txt · Best target for: stripping formatting, scripting.
HTML — Web document
The format the web is built on. Good for content meant to be read in a browser, embedded in an email, or processed by a static-site generator. Convert HTML to PDF to snapshot a page exactly as it looks today.
MIME: text/html · Extension: .html, .htm · Best target for: web display, archiving a webpage.
JPG / JPEG — Photographic image
Lossy compression tuned for photographs. Tiny files, good quality at moderate compression, no transparency. Use for photos, social media uploads, and any image you don't need to edit further. Bad for screenshots, diagrams, and anything with sharp edges or text — the compression artifacts show up as smudges around hard transitions. Need a JPG inside a PDF wrapper? JPG → PDF makes a single-page PDF sized to the image.
MIME: image/jpeg · Extension: .jpg, .jpeg · Best target for: photographs.
PNG — Lossless image
Lossless compression with full alpha-transparency support. The right format for screenshots, logos, icons, diagrams, and anything that needs crisp edges or a transparent background. Larger files than JPG for photos, but every pixel is preserved exactly. Need a PNG inside a PDF wrapper? PNG → PDF makes a single-page PDF sized to the image; transparency is flattened onto a white background because PDF can't carry per-pixel alpha at this layer.
MIME: image/png · Extension: .png · Best target for: screenshots, logos, transparency.
GIF — Graphics Interchange Format
Old format, still alive thanks to animated GIFs. Capped at 256 colors, so terrible for photographs but fine for simple animations and very small UI graphics. We support GIF as a still-image source and target; animation is preserved on convert-to-GIF where the source supports it.
MIME: image/gif · Extension: .gif · Best target for: short loops, very simple graphics.
BMP — Bitmap image
An uncompressed Windows raster format. Files are huge — a 4K BMP is around 30 MB — but every pixel is stored verbatim. Mostly useful when a legacy tool or printer driver demands BMP. We currently support BMP as an OCR source (drop a BMP, get the text out) — image-to-image conversion for BMP is on the roadmap; request it if you need it.
MIME: image/bmp · Extension: .bmp · Best target for: legacy tooling that requires it.
TIFF — Tagged Image File Format
The professional scanning, archival, and print format. Supports lossless compression, multi-page documents, and arbitrary bit depths. Common in publishing, medical imaging, and document archival pipelines. We currently support TIFF as an OCR source (great for scanned documents); image-to-image conversion for TIFF is on the roadmap.
MIME: image/tiff · Extension: .tif, .tiff · Best target for: archival, multi-page scans, print.
WebP — Modern web image
Google's image format. Roughly 25–35% smaller than JPG at the same quality, with lossless and transparent variants too. Supported in every modern browser. The right default for new web projects — for older systems, fall back to PNG or JPG. Convert WebP to JPG or PNG for editor or print hand-off; go the other way with JPG → WebP or PNG → WebP to ship smaller files on the web.
MIME: image/webp · Extension: .webp · Best target for: the modern web.
HEIC — iPhone photo (HEIF)
Apple's default photo format since iOS 11. HEIC files are roughly half the size of equivalent JPGs at the same quality, but the codec underneath (HEVC) is patent-encumbered, so Windows and most non-Apple apps can't open them out of the box. We convert HEIC to JPG, PNG, or PDF — EXIF orientation is honored so iPhone photos don't come out sideways.
MIME: image/heic · Extension: .heic, .heif · Best target for: the iPhone camera roll itself; convert before sharing.
OCR — Extract text
Not a file format but a conversion mode. Pick OCR as the target for an image or PDF and you'll get a plain-text file back, with the readable text pulled out by Google Cloud Vision. Accuracy is high on clean, high-contrast scans and drops on faint, skewed, or handwritten pages. More on how OCR works.
Output: .txt · Best for: turning a scanned PDF or photo into searchable, copyable text.
Picking the right format
- For final, polished documents: PDF.
- For documents you'll keep editing: DOCX.
- For photographs on the web: WebP first, JPG as fallback.
- For screenshots, logos, and diagrams: PNG, or WebP if file size matters.
- For archival or print scans: TIFF.
- For pulling text out of an image or scanned PDF: OCR.
Still not sure? Try the conversion you think you want — files are auto-deleted in an hour, so there's no risk in experimenting.