How many pixels is 1 inch at 300 DPI?

At 300 DPI, 1 inch = 300 pixels. This is the professional print standard. So a 2×2 inch photo at 300 DPI = 600×600 pixels. A 35×45mm passport photo at 300 DPI = approximately 413×531 pixels.

How do I calculate pixels for a passport photo?

Indian passport photo = 35×45mm at 300 DPI = 413×531 pixels. US passport photo = 2×2 inches at 300 DPI = 600×600 pixels. Use our Print Size Calculator tab — enter 35mm × 45mm at 300 DPI and it instantly shows the required pixel dimensions.

What is the pixel size of IBPS exam photos?

IBPS exam photos require 200×230 pixels in JPEG format with a maximum file size of 100KB. At 96 DPI, 200×230 pixels prints at 2.08×2.40 inches. At 300 DPI, the same pixel count prints at 0.67×0.77 inches — the correct physical passport size.

How do I calculate megapixels from pixel dimensions?

Megapixels = (Width × Height) ÷ 1,000,000. For example, a 4000×3000 pixel image = 12,000,000 pixels = 12 megapixels. Our Megapixel Calculator tab handles this instantly, also showing the storage requirement and equivalent camera sensor size.

How do I calculate aspect ratio from pixel dimensions?

Aspect ratio = Width ÷ GCD(Width, Height) : Height ÷ GCD(Width, Height). For a 1920×1080 image, GCD=120, so aspect ratio = 16:9. Our Aspect Ratio Calculator shows the simplified ratio, decimal ratio, and whether the image is landscape, portrait, or square.

How do I estimate image file size from pixel dimensions?

Estimated file size depends on format and compression: PNG (lossless) ≈ Width × Height × 3 bytes ÷ 2 (compression). JPEG at 90% quality ≈ Width × Height × 0.1 bytes. RAW ≈ Width × Height × 3 bytes. Our File Size Estimator shows estimates for JPEG (multiple qualities), PNG, and RAW simultaneously.

What resolution do I need to print at a specific size?

Required pixels = Print Size (inches) × DPI. For a 4×6 inch print at 300 DPI, you need 1200×1800 pixels minimum. For a 5×7 inch print at 300 DPI, you need 1500×2100 pixels. Our Print Size calculator shows minimum pixels for any print size and DPI combination.

How do I convert pixels to cm?

cm = (Pixels ÷ DPI) × 2.54. For example, 413 pixels at 300 DPI = 413÷300 = 1.377 inches × 2.54 = 3.498 cm ≈ 35mm. Our calculator converts pixels to cm, mm, inches, points, and picas simultaneously at any DPI.

What is the difference between screen resolution and print resolution?

Screen resolution is measured in PPI (Pixels Per Inch) on a monitor — typically 72–227 PPI for modern displays. Print resolution is measured in DPI (Dots Per Inch) — 300 DPI is the professional print standard. The same image will appear larger on screen than in print because screen PPI is lower than print DPI. A 600×600px image on a 96 PPI screen appears 6.25×6.25 inches, but prints at only 2×2 inches at 300 DPI.

How many pixels do I need for social media profile photos?

Common social media image size requirements: Instagram profile photo 320×320px (displayed), Instagram post 1080×1080px, Facebook profile 180×180px, Twitter/X profile 400×400px, LinkedIn profile 400×400px, WhatsApp profile 500×500px. Our Social Media Preset tab shows exact pixel requirements for all major platforms.

What is screen PPI and how do I calculate it?

PPI (Pixels Per Inch) = √(Width² + Height²) ÷ Screen Size (diagonal inches). For a 1920×1080 display with a 15.6-inch screen: diagonal pixels = √(1920²+1080²) = 2203, PPI = 2203÷15.6 = 141 PPI. Our Screen PPI Calculator tab does this instantly — enter your screen resolution and diagonal size.

How do I calculate the resolution needed for a specific print DPI?

Required Width (pixels) = Print Width (inches) × DPI. Required Height (pixels) = Print Height (inches) × DPI. For an A4 page (8.27×11.69 inches) at 300 DPI: 2481×3507 pixels. At 150 DPI: 1240×1754 pixels. Use our Print Resolution calculator to get exact pixel requirements for any paper size and DPI.

How do I resize an image to specific pixel dimensions?

Use our IBPS Photo Resizer, SSC Photo Resizer, or Passport Photo Maker tools after calculating the exact pixel dimensions needed using this Pixel Calculator. Our full suite of resizing tools handles all major exam portals and international passport photo requirements.

What are typographic points and picas in pixel terms?

At 72 DPI (the typographic standard): 1 point = 1 pixel, 1 pica = 12 pixels = 12 points. At 96 DPI (screen standard): 1 point = 1.333 pixels, 1 pica = 16 pixels. At 300 DPI (print): 1 point = 4.167 pixels, 1 pica = 50 pixels. Our Pixel Calculator converts to points and picas at any DPI for typography and design workflows.

What is the pixel size of A4 paper at different DPIs?

A4 paper is 210×297mm (8.27×11.69 inches). At 72 DPI: 595×842 pixels. At 96 DPI: 794×1123 pixels. At 150 DPI: 1240×1754 pixels. At 300 DPI: 2480×3508 pixels. At 600 DPI: 4960×7016 pixels. Our Standard Presets include A4 and all common paper sizes.

Pixel Calculator – Pixels to Inches, cm, mm | DPI Calculator | Resolution & Megapixel Tool 2026

Q: How do I convert pixels to inches?

Use the formula: Inches = Pixels ÷ DPI. For example, 300 pixels at 300 DPI = 1 inch. At 96 DPI (standard screen), 300 pixels = 3.125 inches. Our Pixel Calculator does this instantly — enter your pixel count and DPI and get the result in inches, cm, mm, points, and picas simultaneously.

📏 Pixels → Physical Units

Width (px)

Height (px)

DPI / PPI

🔢 Physical Units → Pixels

Unit

Width (mm)

Height (mm)

DPI / PPI

🖨️ Required Pixels for Print

Width

Height

Unit

📄 Print Size from Pixels

Width (px)

Height (px)

Your DPI

📷 Pixel Dimensions → Megapixels

Width (px)

Height (px)

🔢 Megapixels → Dimensions

Megapixels (MP)

Aspect Ratio

⊞ Pixels → Aspect Ratio

Width (px)

Height (px)

🔄 New Dimensions from Ratio

Lock one dimension and calculate the other to maintain aspect ratio.

Original W (px)

Original H (px)

New Width (px)

New Height (px)

💾 Image File Size Estimator

Estimate storage requirements before shooting or after resizing. Results are approximate — actual file size varies with image content and encoder.

Width (px)

Height (px)

Colour Depth

🖥️ Screen PPI Calculator

Screen Width (px)

Screen Height (px)

Screen Size (diagonal inches)

📱 Device-to-CSS Pixel Ratio

Modern high-DPI screens use a device pixel ratio (DPR) — each CSS pixel maps to multiple physical pixels. This is why Retina images need 2× resolution.

CSS Pixel Width

CSS Pixel Height

Device Pixel Ratio (DPR)

📱 Responsive Breakpoint & Image Size Calculator

Calculate the correct image dimensions across all responsive breakpoints for web development. Enter your base (largest) image size and get pixel requirements for all standard CSS breakpoints.

Full Width (px)

Full Height (px)

Max Display Width (CSS px)

Pixel Calculator – The Complete Guide to Pixel Conversions, DPI & Image Dimensions (2026)

Our Pixel Calculator is the most comprehensive, free pixel measurement tool available — combining 10 specialized calculators in a single, instant, browser-based tool. Whether you need to convert pixels to physical dimensions for printing, calculate megapixels for a camera sensor, determine the aspect ratio of a video frame, estimate file storage requirements, check screen PPI, plan responsive web images, or find the exact pixel requirements for 50+ exam portal and social media presets — this is your complete pixel calculation workstation.

📏

Pixels ↔ 5 Units

Convert pixels to inches, cm, mm, typographic points and picas at any DPI — and back. Instant bidirectional conversion.

🖨️

Print Size Calculator

Calculate exact pixel requirements for any print size at any DPI. Or input pixels and get print dimensions at 5 DPI values.

📷

Megapixel Calculator

Calculate megapixels from pixel dimensions. Or reverse-calculate pixel dimensions from MP count and aspect ratio.

⊞

Aspect Ratio Tool

Get simplified ratio, decimal ratio, orientation. Scale to new dimensions while locking aspect ratio perfectly.

💾

File Size Estimator

Estimate JPEG, PNG, RAW, TIFF, WebP file sizes at multiple quality levels before saving or uploading.

🖥️

Screen PPI + DPR

Calculate screen pixels-per-inch from resolution and diagonal size. Calculate physical pixel requirements at any device pixel ratio.

The Core Formula: Pixels, DPI & Physical Size

Every pixel calculation comes down to one fundamental relationship between three values. Understanding this equation is the foundation of all image measurement work:

Physical Size (inches) = Pixels ÷ DPI
Pixels = Physical Size (inches) × DPI
DPI = Pixels ÷ Physical Size (inches)

Physical Size (cm) = (Pixels ÷ DPI) × 2.54
Physical Size (mm) = (Pixels ÷ DPI) × 25.4
Physical Size (pt) = (Pixels ÷ DPI) × 72
Physical Size (pc) = (Pixels ÷ DPI) × 6

Pixel to Inch Conversion at All Standard DPI Values

Pixels	At 72 DPI	At 96 DPI	At 150 DPI	At 300 DPI ★	At 600 DPI
72 px	1.000 inch	0.750 inch	0.480 inch	0.240 inch	0.120 inch
96 px	1.333 inch	1.000 inch	0.640 inch	0.320 inch	0.160 inch
200 px	2.778 inch	2.083 inch	1.333 inch	0.667 inch	0.333 inch
300 px	4.167 inch	3.125 inch	2.000 inch	1.000 inch	0.500 inch
413 px	5.736 inch	4.302 inch	2.753 inch	1.377 inch (35mm)	0.688 inch
600 px	8.333 inch	6.250 inch	4.000 inch	2.000 inch	1.000 inch
1200 px	16.667 inch	12.500 inch	8.000 inch	4.000 inch	2.000 inch
1920 px	26.667 inch	20.000 inch	12.800 inch	6.400 inch	3.200 inch
2480 px	34.444 inch	25.833 inch	16.533 inch	8.267 inch (A4★)	4.133 inch
3000 px	41.667 inch	31.250 inch	20.000 inch	10.000 inch	5.000 inch

Pixel Dimensions for Every Major Indian Exam Portal

Exam / Portal	Pixels (W×H)	Physical Size	Max File Size	Format	Effective DPI
IBPS PO/Clerk/SO/RRB	200×230	~17×19 mm at 300 DPI	100 KB	JPEG	~295 DPI
SBI PO / Clerk	200×230	~17×19 mm at 300 DPI	50 KB	JPEG	~295 DPI
UPSC Civil Services	340×410	~29×35 mm at 300 DPI	300 KB	JPEG	~295 DPI
NTA – NEET / JEE Main	200×230	~17×19 mm at 300 DPI	100 KB	JPEG	~295 DPI
SSC CGL / CHSL / GD	200×230	~17×19 mm at 300 DPI	100 KB	JPEG	~295 DPI
RRB NTPC / Group D	200×230	~17×19 mm at 300 DPI	100 KB	JPEG	~295 DPI
India Passport (PSP)	413×531	35×45 mm at 300 DPI	1 MB	JPEG	300 DPI
US Passport (2×2″)	600×600	51×51 mm at 300 DPI	240 KB	JPEG	300 DPI
UK Passport	413×531	35×45 mm at 300 DPI	—	JPEG	300 DPI
Schengen Visa (EU)	413×531	35×45 mm at 300 DPI	—	JPEG	300 DPI
Canada Passport	591×827	50×70 mm at 300 DPI	—	JPEG	300 DPI
RBI Grade B / NABARD	200×230	~17×19 mm	50 KB	JPEG	~295 DPI

Standard Print Sizes – Pixels Required at 300 DPI

Print Size	mm (W×H)	At 150 DPI	At 200 DPI	At 300 DPI ★	At 600 DPI
Passport Photo	35×45	207×266	276×354	413×531	827×1063
Wallet 2×2.5″	51×63	300×371	400×496	600×744	1200×1488
4×6 inch	102×152	600×900	800×1200	1200×1800	2400×3600
5×7 inch	127×178	750×1050	1000×1400	1500×2100	3000×4200
6×8 inch	152×203	900×1200	1200×1600	1800×2400	3600×4800
8×10 inch	203×254	1200×1500	1600×2000	2400×3000	4800×6000
A5 (148×210mm)	148×210	874×1240	1165×1654	1748×2480	3496×4960
A4 (210×297mm)	210×297	1240×1754	1654×2339	2480×3508	4960×7016
A3 (297×420mm)	297×420	1754×2480	2339×3307	3508×4961	7016×9921
11×14 inch	279×356	1650×2100	2200×2800	3300×4200	6600×8400

Social Media Image Pixel Dimensions – All Platforms (2026)

📸 Instagram

Profile Photo: 320×320px (min) — displayed at 110×110px
Square Post: 1080×1080px (recommended)
Portrait Post: 1080×1350px (4:5 ratio)
Landscape Post: 1080×566px (1.91:1 ratio)
Story / Reel: 1080×1920px (9:16 ratio)
Carousel: 1080×1080px per slide

📘 Facebook

Profile Photo: 180×180px (min)
Cover Photo: 820×312px (desktop) / 640×360px (mobile)
Shared Image: 1200×630px (recommended)
Story: 1080×1920px
Event Cover: 1920×1080px

🐦 Twitter / X

Profile Photo: 400×400px
Header: 1500×500px
Tweet Image: 1200×675px (16:9)
Card Image: 800×418px

💼 LinkedIn

Profile Photo: 400×400px
Background / Banner: 1584×396px
Shared Image: 1200×627px
Company Logo: 300×300px

▶️ YouTube

Channel Icon: 800×800px
Channel Art: 2560×1440px
Thumbnail: 1280×720px (16:9)
Video: 1920×1080px (HD), 3840×2160px (4K)

💬 WhatsApp

Profile Photo: 500×500px (recommended)
Status Image: 1080×1920px
Shared Image: No strict limit, compress to <16MB

🎵 TikTok

Profile Photo: 200×200px (min)
Video: 1080×1920px (9:16 vertical)
Cover Image: 1080×1920px

Common Screen Resolutions & Their PPI

Device / Standard	Resolution	Screen Size	PPI	Category
iPhone 16 Pro	2556×1179	6.3 inch	460 PPI	Super Retina XDR
iPhone 15 / 16	2556×1179	6.1 inch	460 PPI	Super Retina XDR
Samsung Galaxy S24 Ultra	3088×1440	6.8 inch	505 PPI	Dynamic AMOLED
MacBook Pro 16″ M3	3456×2234	16.2 inch	254 PPI	Liquid Retina XDR
MacBook Air 13″	2560×1664	13.6 inch	224 PPI	Liquid Retina
4K UHD Monitor 27″	3840×2160	27 inch	163 PPI	4K UHD
QHD Monitor 27″	2560×1440	27 inch	109 PPI	QHD / 1440p
FHD Laptop 15.6″	1920×1080	15.6 inch	141 PPI	Full HD
Standard HD Screen	1366×768	15.6 inch	100 PPI	HD
iPad Pro 12.9″	2732×2048	12.9 inch	264 PPI	Liquid Retina

Understanding Aspect Ratios – Complete Reference

📺 Common Aspect Ratios Explained

1:1 (Square): Instagram posts, profile photos, thumbnail icons. 600×600, 1080×1080, 2000×2000
4:3 (Standard): Traditional TV, computer monitors, older cameras. 800×600, 1024×768, 4000×3000
3:2 (Photo): 35mm film, DSLR cameras, APS-C sensors. 3000×2000, 4500×3000, 6000×4000
16:9 (Widescreen): HD video, YouTube, modern TV, most laptop screens. 1280×720, 1920×1080, 3840×2160
9:16 (Vertical): Instagram Stories, Reels, TikTok, YouTube Shorts. 1080×1920
3:4 (Portrait): Portrait photography, Instagram portrait posts. 1080×1440
2:3 (Tall Portrait): Portrait mode photos. 2000×3000
1.91:1 (Landscape web): Facebook/Twitter shared images. 1200×628

📐 Passport Photo Aspect Ratios

India / EU Passport (35×45mm): Ratio = 7:9 ≈ 0.778:1 (portrait)
US Passport (2×2 inch / 51×51mm): Ratio = 1:1 (square)
Canada Passport (50×70mm): Ratio = 5:7 ≈ 0.714:1 (portrait)
IBPS / SSC / NTA (200×230px): Ratio = 20:23 ≈ 0.87:1 (portrait)
UPSC (340×410px): Ratio = 34:41 ≈ 0.829:1 (portrait)

📏 Aspect Ratio Tip: Maintain aspect ratio when resizing to avoid stretching or squishing. Our Aspect Ratio tab's "Scale Dimensions" tool calculates the correct new dimensions automatically when you change one axis.

File Size Estimation – How Image Storage is Calculated

Understanding how image file size is calculated helps you plan storage, optimize uploads, and choose the right format for each use case:

Uncompressed size (bytes) = Width × Height × (Bits per pixel ÷ 8)
24-bit RGB uncompressed = Width × Height × 3 bytes
JPEG estimate (~90% quality) = Width × Height × 0.08 bytes (≈ 1/37 of raw)
PNG estimate (lossless) = Width × Height × 1.5 bytes (natural photos)
PNG estimate (graphics) = Width × Height × 0.4 bytes (flat colour)
WebP estimate = Width × Height × 0.06 bytes (similar to JPEG at 90%)
RAW / TIFF (24-bit) ≈ Width × Height × 3 bytes (uncompressed)

pixel calculator pixels to inches calculator pixels to cm converter pixels to mm online dpi pixel calculator megapixel calculator aspect ratio calculator print size calculator image resolution calculator screen ppi calculator file size estimator responsive image calculator how many pixels per inch 300 dpi pixel calculator exam photo pixel size ibps photo pixels passport photo pixel dimensions pixel calculator for printing a4 pixels at 300 dpi social media image size calculator

Frequently Asked Questions – Pixel Calculator

How do I convert pixels to inches?

The formula is Inches = Pixels ÷ DPI. For example, 600 pixels at 300 DPI = 600 ÷ 300 = 2 inches. At 96 DPI (standard screen), 600 pixels = 6.25 inches. Use the Pixels ↔ Units tab in our calculator — enter your pixel width, height, and DPI to get instant results in inches, cm, mm, points, and picas simultaneously.

How many pixels are in 1 cm at 300 DPI?

At 300 DPI: 1 cm = 118.11 pixels (300 ÷ 2.54 = 118.11). At 96 DPI: 1 cm = 37.8 pixels. At 72 DPI: 1 cm = 28.35 pixels. So a 35mm wide passport photo at 300 DPI = 35 × 118.11 ÷ 10 ≈ 413 pixels wide. Our calculator handles all these conversions instantly.

What pixel size is 35×45mm at 300 DPI?

35×45mm at 300 DPI = 413×531 pixels. Formula: Width = 35mm ÷ 25.4mm/inch × 300 DPI = 413.39 ≈ 413px. Height = 45mm ÷ 25.4 × 300 = 531.5 ≈ 531px. This is the standard Indian passport photo size. Use the Physical Units → Pixels tab and enter 35mm × 45mm at 300 DPI.

What is the pixel size of A4 paper at 300 DPI?

A4 paper (210×297mm) at 300 DPI = 2480×3508 pixels. This is the standard resolution for professional A4 document printing. At 150 DPI: 1240×1754px. At 72 DPI: 595×842px (PDF screen resolution). Use the Print Size tab and select the A4 preset.

How do I calculate megapixels?

Megapixels = (Width × Height) ÷ 1,000,000. A 4000×3000 pixel image has 4000 × 3000 = 12,000,000 pixels = 12 megapixels. A 200×230 pixel exam photo has 46,000 pixels = 0.046 megapixels. Use the Megapixels tab for instant calculation plus maximum print size analysis.

How do I maintain aspect ratio when resizing?

Use the Aspect Ratio tab → Scale Dimensions section. Enter your original width and height, then enter either the new width OR new height — the other dimension is automatically calculated to maintain the exact aspect ratio. This prevents stretching or squishing your image. For example: original 1920×1080, new width 800 → new height = 800 × (1080÷1920) = 450px.

What does 300 DPI mean for photo printing?

300 DPI means 300 pixels are printed per inch. It is the professional standard for photo printing — at 300 DPI, individual dots are invisible to the naked eye at normal viewing distances, resulting in smooth, sharp prints. For a 4×6 inch print at 300 DPI you need 1200×1800 pixels minimum. Below 150 DPI, prints start to look visibly soft or pixelated.

What is the IBPS exam photo pixel size?

IBPS exam photos must be 200×230 pixels in JPEG format with a maximum file size of 100KB. At 300 DPI, 200×230 pixels prints at 0.67×0.77 inches (approximately 17×19mm) — the physical size of a standard passport photo. Use the Presets tab and select "IBPS / SSC / NTA" for instant pixel reference and our IBPS Photo Resizer to resize your actual photo.

How do I calculate screen PPI?

PPI = √(Width² + Height²) ÷ Screen diagonal (inches). For a 1920×1080 screen on a 15.6" laptop: diagonal pixels = √(1920²+1080²) = √(3686400+1166400) = √4852800 = 2203px. PPI = 2203 ÷ 15.6 = 141 PPI. Use the Screen PPI tab for instant calculation — just enter resolution and screen size.

How do I estimate JPEG file size from pixel dimensions?

JPEG file size varies with image content and compression level. A rough estimate at 90% JPEG quality: File size ≈ Width × Height × 0.08 bytes. For a 1200×1800px image: 1200 × 1800 × 0.08 = 172,800 bytes ≈ 169 KB. Use the File Size Estimator tab for estimates at multiple JPEG quality levels plus PNG, WebP, and RAW simultaneously.

What pixel size do I need for a 2-megapixel, 12-megapixel, or 48-megapixel image?

At 4:3 aspect ratio: 2MP ≈ 1632×1224px · 8MP ≈ 3264×2448px · 12MP ≈ 4000×3000px · 16MP ≈ 4608×3456px · 20MP ≈ 5152×3864px · 48MP ≈ 8000×6000px. At 16:9: 2MP ≈ 1882×1059px · 12MP ≈ 4619×2598px. Use the Megapixels → Dimensions tab for exact calculations at any aspect ratio.