Merge BMP to PDF

How to Merge BMP to PDF Online

1. Upload Your BMP Files: Drag and drop or click "Add Files" to select multiple .bmp bitmaps. Reorder them by dragging — the sequence becomes your PDF page order. Batch is supported.
2. Pick Combine Mode and Page Layout: Default is Single PDF (one merged document) — switch to Individual PDFs to get one PDF per BMP. Choose Page layout Portrait (default) or Landscape, and pick a Paper size (A4 default; LETTER, LEGAL, A3, TABLOID, LEDGER, EXECUTIVE, ARCH A/B, ISO B4/B5, or Original to match each bitmap's pixel dimensions).
3. Tune Image Placement, Margin, and Compression (Optional): Image placement Cover (fills the page, may crop) or Contained (default; fits inside margins with letterboxing). Image alignment Top, Center (default), or Bottom. Margin Narrow 0.5" (default), No margin, Moderate 0.75x1", Normal 1", or Large 2x1". Image Quality slider 1-100 (default 75) controls JPEG re-encoding inside the PDF; raise toward 100 for archival, lower toward 30 to shrink heavy bitmap dumps. Image Transparency Unchanged or Removed (flatten alpha onto white).
4. Merge and Download: Click Merge. Files process in your browser session — no sign-up, no watermark, no email required.

Why Merge BMP to PDF?

BMP (Windows Bitmap) is Microsoft's uncompressed raster format, introduced with Windows 1.0 in November 1985 and formalized alongside Windows 2.0 in 1987. Because 24-bit BMP stores three raw bytes per pixel with no entropy coding, a single 1920x1080 screenshot weighs roughly 5.9 MB (1920 x 1080 x 3 = 6,220,800 bytes), and a 4K capture pushes past 23 MB. A folder of those bitmaps is painful to email, link, or archive. Wrapping them in a PDF (ISO 32000, standardized by ISO in July 2008) gives you one portable file that opens identically on Windows, macOS, iOS, Android, and any modern browser, with the embedded images JPEG-compressed at the quality you choose.

• Windows screenshot bundles — Print Screen on older Windows builds and many industrial HMIs still drop .bmp files. Merging twenty Windows 7/Server screenshots at Quality 75 typically takes a 100+ MB folder down to a 5-15 MB shareable PDF.
• Legacy app and CAD output — Older line-of-business apps, AutoCAD plot drivers, and lab instruments often export BMP because the format is trivial to write. Combining a day's plots into one A3 Landscape PDF gives engineering teams a paginated artifact instead of loose bitmap files.
• Scanned documents and forms — TWAIN drivers and older flatbed scanners (HP, Canon, Epson) frequently default to .bmp at 300 DPI. Merging the pages into a single A4 Portrait PDF with Narrow margins matches the look of a native document scan.
• Medical, microscopy, and industrial imaging — Older microscope cameras, ultrasound consoles, and inspection rigs export BMP to preserve pixel-exact data. A Letter Cover-placement PDF at Quality 90+ keeps the image faithful while making the case file easy to attach to a chart.
• Game and emulator screenshots — DOSBox, ScummVM, and several retro-game capture tools save .bmp by default. A merged PDF is a clean way to ship a bug report or a "let's play" gallery.
• Archival and offline storage — PDF/A-bound workflows, court e-filing portals, and university LMS uploads typically reject .bmp but accept PDF. Merging is the fastest path to a compliant submission.

BMP vs PDF (Image-Wrapped) — Format Comparison

Image Quality Slider Quick Guide

Frequently Asked Questions

How much smaller will my PDF be than the BMP folder?

Usually 70-95 percent smaller. A 24-bit 1920x1080 BMP is about 5.9 MB raw because every pixel is stored as three uncompressed bytes (1920 x 1080 x 3 = 6,220,800 bytes). The same image embedded in a PDF at Image Quality 75 typically lands at 150-400 KB — it's re-encoded with JPEG inside the document. Screenshots of dialog boxes and text compress even harder; photo-heavy bitmaps compress less.

Will the PDF be lossless?

No, not at the default settings. The Image Quality slider re-encodes embedded images as JPEG, which is lossy. If you need pixel-exact preservation of the original BMP, push Quality to 95-100 (still technically lossy, but visually indistinguishable on a monitor) or convert each BMP to PNG first with BMP to PNG and then merge — PNG inside PDF uses Flate compression and is fully lossless.

Should I pick Cover or Contained image placement?

Use Contained (default) when your bitmaps have varied aspect ratios — screenshots, scanned forms, and CAD plots — so the whole image always fits inside the page with safe margins. Use Cover when every BMP shares the same aspect ratio as the chosen Paper size (for example, 16:9 screenshots on a Landscape page) and you want edge-to-edge output with no white border. Cover will crop anything that doesn't match the page ratio.

Why is "Original" paper size useful?

Selecting Original (which maps to "same as image size" internally) makes each PDF page exactly the pixel dimensions of the BMP it wraps, so a 3000x2000 scan becomes a 3000x2000-point page. That's ideal when you don't want any letterboxing, cropping, or rescaling — common for archival scans, comic-page workflows, and pixel-art collections. The downside is that page sizes vary across the document, which some printers handle poorly.

What does "Image Transparency: Removed" do?

32-bit BMP can store an alpha channel (8 bits per pixel for transparency). Most BMPs in the wild are 24-bit and have no alpha, so this setting has no effect. For 32-bit BMPs with transparency, "Removed" composites the image onto a white background before embedding, which prevents PDF viewers that don't support image transparency from rendering grey or black behind the alpha pixels. Leave it on Unchanged if you're not sure.

Can I merge BMP with other image formats in one PDF?

Not on this page — merge-bmp-to-pdf only accepts .bmp inputs. If you have a mix, convert your other images to BMP first, or use Merge JPG to PDF or Merge PNG to PDF for those source formats. A future enhancement could allow mixed inputs through the generic image-merge endpoint, but today the page is type-locked.

Is there a file size or page count limit?

Browser-based processing means the practical limit is your device's RAM, not a server quota. Most users can merge 50-150 BMPs comfortably on a modern laptop. If you're combining hundreds of high-resolution scans (300+ MB of input), close other tabs first, or split the job into two batches and concatenate the resulting PDFs afterward.

Why is my PDF still huge after merging?

Two common causes: (1) you set Image Quality to 95-100, which keeps the JPEG re-encode near-lossless and produces large pages — drop to 75 for a typical 5-10x size reduction; (2) your BMPs are very high-resolution scans (4800 DPI or 4K-plus dimensions) and even compressed JPEG pages are ~1-2 MB each. For a slimmer file, compress the merged PDF afterward, or downscale the BMPs first with Compress BMP.

Does the PDF preserve the BMP's original color profile?

The merged PDF does not copy the BMP's embedded ICC profile by default — embedded images are re-encoded into a generic sRGB-tagged JPEG. For prepress or color-critical work where ICC fidelity matters, use Compression Type "Prepress" if exposed, keep Quality at 95+, and verify the output in a calibrated viewer. For most office, web, and screenshot use cases, the default sRGB pipeline is correct and indistinguishable from the source.