What JPEG quality should I use for BMP to JPG conversion?

Quality 85 is the standard recommendation for photographs — excellent visual quality at roughly 10–20× compression over BMP. Use 75 for web thumbnails where file size matters more. Use 92–95 for near-lossless archival quality. Never go below 60 unless extreme compression is required.

When should I NOT convert BMP to JPG?

Avoid converting BMP to JPG when your image has text, sharp lines, logos, or flat colors — JPEG compression creates visible artifacts around these. Use PNG instead. Also avoid JPEG if you need to edit and re-save many times (quality degrades each round-trip). For screenshots, always use PNG, not JPEG.

How to Convert BMP to JPG — 7 Methods (Browser, Windows, Mac, CLI)

Q: How do I convert BMP to JPG for free?

Use Convertlo's free browser converter at convertlo.pro — select Image tab, choose BMP input and JPG output, drop your file, download the result. No upload, no signup, converts in under a second. Windows Paint is another free option: open the BMP, go to File → Save As → JPEG picture.

Q: How much smaller is JPG than BMP?

Dramatically smaller. A 1920×1080 24-bit BMP is always exactly 5.93 MB. The same image converted to JPEG at quality 85 is typically 300–600 KB — about 10–20× smaller. For photographs with many colors and gradients, the reduction can reach 93% or more.

Q: Does converting BMP to JPG lose quality?

Yes — JPEG is lossy. At quality 85, the difference is invisible for photographs. At quality 75 or lower, compression artifacts (blocky regions, color banding near edges) become visible. For screenshots, logos, or text images, even small quality loss is noticeable — use PNG instead of JPEG for those.

Q: How do I batch convert BMP to JPG?

Convertlo's browser converter supports batch: drop multiple BMP files at once, convert, and download a ZIP. IrfanView (Windows) supports batch via File → Batch Conversion. ImageMagick CLI: 'for f in *.bmp; do convert "$f" -quality 85 "${f%.bmp}.jpg"; done'

BMP Guide May 30, 2026 8 min read ·Last updated: Jun 4, 2026

Quick answer — convert BMP to JPG in 30 seconds: Use the free browser converter — no upload, no signup, works offline. Drop your BMP, set quality (85 is the sweet spot), click Convert. A 5.93 MB BMP becomes ~400 KB as JPEG Q85 — 93% smaller. Need Windows built-in? Paint works: File → Save As → JPEG. Mac? Preview: File → Export → JPEG. Batch and CLI options below.

93%

typical file size reduction

5.93 MB

1080p BMP size

~400 KB

same image as JPEG Q85

methods covered

BMP is the heaviest common image format — it stores every pixel raw with zero compression. A single 1920×1080 screenshot is always 5.93 MB as BMP. Converting to JPEG at quality 85 drops that to roughly 300–600 KB for a photograph, while keeping the image visually identical to the naked eye. Below are every practical method for doing it, from the fastest to the most flexible.

Why BMP Files Are So Large

BMP calculates its size by a simple formula: width × height × bits per pixel ÷ 8. A 1920×1080 image at 24-bit color = 1920 × 1080 × 3 bytes = 6,220,800 bytes = 5.93 MB. No matter the content — a solid blue rectangle or a photograph — the file size is identical. BMP stores every pixel individually, in order, with no attempt to find patterns or reduce redundancy.

JPEG works the opposite way. It divides the image into 8×8 pixel blocks and applies Discrete Cosine Transform (DCT) to find which frequency components human vision is least sensitive to, then discards them. The result: photographs compress 10–30× over BMP with barely perceptible quality loss at quality 85.

When NOT to convert to JPEG: If your BMP contains text, a screenshot, a logo, or flat colors — JPEG compression creates visible blocky artifacts (called "ringing") around sharp edges. For those images, convert to PNG instead — it's lossless and still 5–15× smaller than BMP.

JPEG Quality Settings — What Number to Use

Quality	BMP → JPG (1080p photo)	Visual Result	Best For
95	5.93 MB → ~1.5 MB	Near-lossless	Archival, professional printing
85	5.93 MB → ~400 KB	Excellent — difference invisible	Default recommendation
75	5.93 MB → ~220 KB	Good — minor artifacts on close inspection	Web thumbnails, email
60	5.93 MB → ~130 KB	Noticeable artifacts	Tiny previews only

The Convertlo browser converter defaults to quality 85. You can type any value from 1–100 in the quality field before converting.

Method 1 — Free Browser Converter (Fastest, No Install)

All platforms Convertlo Browser Converter

Go to convertlo.pro → Image tab with BMP input and JPG output pre-selected
Drag and drop your BMP file (or multiple files) onto the drop zone
Optionally adjust the quality slider (default 85 is recommended)
Click Convert — processing happens entirely in your browser, nothing is uploaded
Click Download to save the JPG (or Download All ZIP for batch)

Batch: drop up to 20 BMP files at once. Works offline once the page has loaded. No signup, no file size limit.

Convert BMP to JPG Free Now

No upload. No signup. Runs in your browser — works offline.

Convert BMP to JPG → BMP to PNG (lossless) →

Method 2 — Windows Paint (Built-In, No Download)

Windows Microsoft Paint

Right-click the BMP file → Open with → Paint (or search "Paint" in Start)
In Paint, click File → Save As
In the "Save as type" dropdown, select JPEG picture
Choose a filename and click Save

Limitation: Paint saves JPEG at a fixed quality (~85) with no way to adjust it. For quality control, use the browser converter or IrfanView.

Method 3 — Windows Photos App

Windows 10/11 Microsoft Photos

Double-click the BMP to open it in Photos
Click the three-dot menu (⋯) at the top right
Select Save as
Change the file type dropdown to JPEG, then save

Photos also has no quality slider — it uses a fixed internal quality. Good for quick one-off conversions.

Method 4 — Mac Preview (Built-In)

macOS Preview

Double-click the BMP to open it in Preview (or right-click → Open With → Preview)
Go to File → Export
In the Format dropdown, choose JPEG
Drag the Quality slider — set it to around 85% for the best balance
Click Save

Preview is the only built-in macOS tool that exposes the JPEG quality slider. Use it when you need control over output file size.

Method 5 — GIMP (Free, Windows/Mac/Linux)

All platforms GIMP

Open GIMP, then File → Open and select your BMP
Go to File → Export As (not "Save As" — that saves in GIMP's native format)
Type a filename ending in .jpg and click Export
In the JPEG Options dialog, set Quality to 85 (or your preferred level)
Click Export

GIMP gives you full control: quality, subsampling, progressive encoding, and smoothing. Best choice if you also need to edit the image before converting.

Method 6 — IrfanView (Windows, Best for Batch)

Windows IrfanView (free)

Download and install IrfanView from irfanview.com (free, no bundleware)
Single file: Open the BMP → File → Save As → JPG → set quality in the dialog → Save
Batch: Go to File → Batch Conversion/Rename
Select Batch conversion, output format JPG, click Options to set quality
Add all your BMP files to the list, choose output folder, click Start Batch

IrfanView is the fastest native Windows tool for batch conversion. It can process hundreds of BMP files to JPEG in seconds.

Method 7 — ImageMagick CLI (Windows/Mac/Linux)

Command Line ImageMagick

Install ImageMagick from imagemagick.org, then use the magick command:

Single file:

magick input.bmp -quality 85 output.jpg

Batch — all BMP files in current folder (Linux/Mac):

for f in *.bmp; do magick "$f" -quality 85 "${f%.bmp}.jpg"; done

Batch — all BMP files (Windows PowerShell):

Get-ChildItem *.bmp | ForEach-Object { magick $_.FullName -quality 85 ($_.BaseName + ".jpg") }

The older convert command also works on Linux/Mac. On Windows use magick to avoid conflict with the system convert utility.

Bonus Method — Python Pillow

Python Pillow Library

Install with pip install Pillow, then:

from PIL import Image

img = Image.open("input.bmp")
img = img.convert("RGB")  # BMP can be RGBA; JPEG has no alpha
img.save("output.jpg", "JPEG", quality=85, optimize=True)

Batch convert all BMP files in a folder:

from PIL import Image
from pathlib import Path

for bmp in Path(".").glob("*.bmp"):
    img = Image.open(bmp).convert("RGB")
    img.save(bmp.with_suffix(".jpg"), "JPEG", quality=85, optimize=True)
    print(f"Converted: {bmp.name}")

The .convert("RGB") call is required — some BMP files have an alpha channel (RGBA) and JPEG doesn't support transparency. The convert step fills transparent areas with black; if you want white, add img = Image.new("RGB", img.size, (255,255,255)); img.paste(src, mask=src.split()[3]) before saving.

Method Comparison

Method	Platform	Quality Control	Batch	Install Required
Convertlo browser	All	Yes (slider)	Yes (ZIP)	No
Windows Paint	Windows	No (fixed ~85)	No	No (built-in)
Windows Photos	Windows 10/11	No	No	No (built-in)
Mac Preview	macOS	Yes (slider)	One at a time	No (built-in)
GIMP	All	Full control	Plugin required	Yes
IrfanView	Windows	Yes	Yes (native)	Yes (free)
ImageMagick CLI	All	Full control	Shell loop	Yes (free)
Python Pillow	All	Full control	Script	Yes (free)

Batch Conversion Tips

If you have dozens or hundreds of BMP files to convert:

Browser: Drop up to 20 BMP files at once into the Convertlo converter — they process in parallel and download as a ZIP.
IrfanView (Windows): Fastest native tool for large batches — can handle hundreds of files in seconds via File → Batch Conversion.
ImageMagick: Best for automated pipelines (CI/CD, scheduled tasks, server-side conversion).
Python Pillow: Best when you also need to resize, watermark, or apply other transformations in the same script.

When NOT to Convert BMP to JPEG

Screenshots and text images: JPEG applies lossy compression to every 8×8 pixel block. Text with sharp black-on-white edges becomes blurry with visible ringing artifacts around each character. Always use PNG for screenshots — it's lossless and still 5–15× smaller than BMP.

Avoid JPEG for these image types:

Screenshots — text becomes blurry, interfaces look degraded
Logos and icons — flat colors show compression banding
Line art and diagrams — thin lines get "fringe" artifacts
Images you'll edit and re-save repeatedly — quality degrades with each JPEG save (generation loss)
Images with transparency — JPEG has no alpha channel; transparent areas fill with white (or black in some tools)

For all of the above, convert your BMP to PNG instead. PNG is lossless (zero quality loss), and at 5–15× smaller than BMP it's almost always a better choice than keeping the BMP.

Related BMP Guides

What is a BMP File? Complete Format Guide — history, file structure, size formula, color depths
BMP vs JPEG — Full Comparison — file size tables, compression explained, when to use each
BMP vs PDF — Key Differences — when to convert a BMP image to a PDF document
How to Open BMP Files — Windows, Mac, iOS, Android, Linux, browser
BMP to PNG Converter — lossless conversion, 5–15× size reduction, zero quality loss

Frequently Asked Questions

How do I convert BMP to JPG for free?

Use Convertlo's free browser converter — no upload, no signup, converts in under a second. Windows users can also use Paint (File → Save As → JPEG picture) or Windows Photos. Mac users can use Preview (File → Export → JPEG with quality slider). All three are completely free.

How much smaller is JPG than BMP?

Dramatically smaller for photographs. A 1920×1080 24-bit BMP is always exactly 5.93 MB. The same photograph as JPEG at quality 85 is typically 300–600 KB — roughly 10–20× smaller. The exact reduction depends on image content: high-detail photos with many colors compress less than simpler images. A 5.93 MB BMP can become as small as 130 KB at JPEG quality 60, though artifacts become visible at that level.

Does converting BMP to JPG lose quality?

Yes — JPEG is lossy. The conversion permanently discards some image information. At quality 85, the difference is invisible to most people for photographs. At quality 75, minor artifacts appear on close inspection. At quality 60, blocky compression artifacts (called DCT artifacts or "mosquito noise") become clearly visible. For screenshots, logos, and text, even quality 95 JPEG shows some degradation — use PNG for those instead.

What JPEG quality should I use when converting BMP to JPG?

Quality 85 is the standard recommendation for photographs — it achieves roughly 10–20× compression over BMP with visually identical results. Use 75 for web thumbnails where page weight matters. Use 92–95 for near-lossless archival quality (still 3–6× smaller than BMP). Never go below 60 unless extreme size reduction is the priority.

How do I batch convert BMP to JPG?

Three options: (1) Drop multiple BMP files into the Convertlo browser converter — processes in parallel, downloads as ZIP. (2) IrfanView on Windows: File → Batch Conversion/Rename, set output to JPG, add all BMP files, click Start. (3) ImageMagick CLI: for f in *.bmp; do magick "$f" -quality 85 "${f%.bmp}.jpg"; done

Can I convert BMP to JPG without installing software?

Yes — the Convertlo browser converter requires no installation and no file upload. It runs the conversion entirely in your browser using JavaScript. Once the page has loaded, it even works offline. Windows users can also use the built-in Paint app (already installed on all Windows versions) without any additional software.