Image Splitter

Load an image, set the columns and rows, and the cut lines and piece sizes appear at once

Image Splitter cuts one image into several files with no overlap. Set the number of columns and rows, or type the width and height of a single piece in px, and cut lines are drawn over the image. The top ruler shows the width of each column and the left ruler shows the height of each row. The sample landscape, 3240 × 1440, split into 3 columns × 2 rows gives six pieces of 1080 × 720.

You can move the cut lines by dragging or with the arrow keys, and "Snap to blank rows" moves each one to a nearby empty row so that text and product photos are not cut through. For an Instagram carousel or profile grid, a single Use button sets the piece ratio and the file numbering, and a preview below shows how the post will look. The image is never sent to a server; it is split inside this browser.

When you need to split an image

• Posting a panorama as a carousel: a wide photo posted as one image looks small on screen. Cut into several pieces of the same ratio and added to one post in order, the scene continues as you swipe sideways. Instagram allows up to 20 photos and videos in a single post.
• Filling a profile grid with one picture (a 9-piece split): split a picture into 3 columns and post the pieces separately, and it reads as one picture again on the profile. A new post is added at the top left, so the posting order is the reverse of the reading order.
• Posting a long product page or screenshot: a long online-store product page or a long chat screenshot is hard to handle as one image. Split it into several images, with the cut lines placed in the gaps between paragraphs, and no line of text is cut across two images.
• Printing a large picture on several A4 sheets: to make a poster on a home or office printer, split the picture into A4-ratio pieces, print them one by one and tape them together. You can check in advance how many dpi each piece gets on one A4 sheet.
• Cutting out repeated cells, such as a sprite sheet: game sprite sheets and icon sets have a fixed cell size. Enter the cell size under Size, for example 64 × 64, and a 1024 × 512 sheet is split into 16 columns × 8 rows, 128 pieces.

How to split an image

1. Add the image: click Open image or drop a file onto the workspace. A copied image can also be pasted (Ctrl+V, ⌘V). One image is split at a time, and adding a new one replaces the previous one.
2. Choose a use: pick one of Custom split, Instagram carousel, Instagram profile grid, Long vertical image or A4 poster print, and the matching count and ratio are filled in. The second line of each button shows how many pieces the current image will make and the size of the first piece.
3. Adjust the count or size: when splitting by Count, enter columns and rows from 1 to 32; when splitting by Size, enter the piece width and height in px. If you choose a piece ratio, the part outside that ratio is cropped, and the center handle moves the area you keep.
4. Check the cut lines: look at the px on the rulers and the position of the cut lines. If a line runs through a face or a line of text, drag it away or snap it to a blank row. "Spread pieces apart" separates the pieces with gaps, and you can click a piece to leave it out of the download.
5. Save: choose a format and the file numbering, then click save. With several pieces you get one ZIP file; with one piece selected you get that single file. In browsers that support file sharing, such as on a phone, the Share button sends the pieces straight to another app.

What do the five uses set for you?

After choosing a use, you can still change the columns, rows or ratio. If the new values break that use's conditions (one row for a carousel; 3 columns and 3:4 for a profile grid), the use switches to Custom split and the Instagram preview closes.

Where do the leftover pixels go when you split evenly?

When you split by Count, the width is divided by the number of columns and the height by the number of rows. Pixels left over because the division is not exact are added 1 px at a time, starting with the leftmost columns and the top rows. Pieces can therefore differ by at most 1 px in width or height, but no blank line is left on the right or at the bottom. When you split by Size, the image is cut from the top left in steps of the size you entered, and only the leftover edge pieces are smaller. The number of pieces across is the width ÷ piece width, rounded up.

In both cases the column widths add up to 1001 and the row heights to 701, so no pixel is lost from the original. The bottom-right piece of the split by Size is 201 × 101; it is not stretched to 400 × 300 or padded with blank space. If every piece must be exactly the same size, make the original a multiple of the piece size or use a piece ratio.

Moving cut lines and "Snap to blank rows"

In Custom split you can move cut lines one by one. Drag a line over the image, drag a handle on the top or left ruler, or select a handle with Tab and move it with the arrow keys, 1 px at a time (10 px with Shift). A cut line cannot cross its neighbors, so no piece ever becomes 0 px, and the numbers on the rulers update immediately. To go back to equal spacing, click "Space evenly".

"Snap to blank rows" uses brightness to decide whether the rows a cut line would cross have any content. The brightness of each pixel is 0.299 × red + 0.587 × green + 0.114 × blue, and a row counts as blank when the difference between its brightest and darkest points is 12 or less. For each cut line it then looks for a run of consecutive blank rows within a quarter of the average piece size, and moves the line to the middle of the run with the most blank rows inside that range, at a spot where the rows just above and below the cut are both blank. If two runs are equally wide, it picks the one closer to the original position.

• Works well on: product pages on a white background, long screenshots with gaps between paragraphs, and charts on a plain color, where some rows are a single color all the way across. Splitting the sample long image (860 × 4800) into 6 rows moves all 5 evenly spaced cut lines into the gaps between paragraphs.
• Does not work well on: landscape photos and backgrounds with gradients or patterns, where rows of a single color are rare. A cut line with no blank row nearby stays where it is, and the tool tells you how many could not be moved, so move those by hand.

What gets cropped when you set a piece ratio?

When you choose a piece ratio (1:1, 4:5, 3:4 or A4), all pieces get the same whole-number size and only the area made by joining them in columns × rows is kept. The piece size is the largest that keeps the ratio and fits in the image. For A4 only, if the cells from a plain column-by-row split already match the ratio within 0.5%, those cells are used as they are, so that rounding does not cut 1 px from sizes such as 2480 × 3508 at 300 dpi. The outer part that is left over is first cropped equally from top and bottom or from left and right, and you can drag the center handle on the stage or use the arrow keys to move the kept area.

If you want to keep the whole image, leave the ratio on "Free". The pieces then follow the image's own ratio, and depending on how Instagram or the printer handles them, the edges may be hidden or margins may appear.

What to know before posting on Instagram

According to Instagram's help pages, one post (a carousel) can hold up to 20 photos and videos, and the orientation you choose (square, portrait or landscape) applies to every slide in that post, so you cannot choose a different one for each slide. Feed photos are uploaded at up to 1,080 px wide, and an aspect ratio between 1.91:1 and 3:4 keeps its original resolution. At 1,080 px wide, 3:4 is 1,440 px tall. For that reason the pieces of a carousel should all have the same ratio, and 3:4 is the right choice when you want the tallest possible view.

Since January 2025, profile grid cells are tall rectangles instead of squares. Instagram head Adam Mosseri explained that most of the photos and videos being posted are vertical, so a tall grid shows them better. However, the exact cell ratio is not given as a number in official documents, so this tool makes pieces at 3:4, the tallest ratio at which feed photos keep their original resolution, and draws the preview with 3:4 cells.

A new post goes to the top left of the grid and pushes earlier posts over by one cell. So the bottom-right piece has to be posted first and the top-left piece last for the picture to line up. With file numbering set to Posting order, the number at the start of each file name follows this sequence (for example, trip_01_r03_c03.jpg is the first one), so you only have to pick the files in numeric order. Because the pieces always fill whole rows of 3, the rows of the new picture stay aligned however many posts you already have. If you have posts pinned to the top of your profile, though, the layout may differ.

Printing a poster on several A4 sheets

An A4 sheet is 210 × 297 mm, and one inch is 25.4 mm. When a piece is printed to fill one A4 sheet, its resolution is dpi = piece px ÷ (paper length in mm ÷ 25.4). For a portrait A4 sheet, a width of 2480 px gives 2480 ÷ (210 ÷ 25.4) ≈ 300 dpi. Choosing A4 poster print shows this value in the result field.

Joined 2 × 2, a portrait poster is 420 × 594 mm. Splitting the same image 3 × 3 lets you make it larger, but the dpi of each sheet drops (a 4032 × 3024 image split 3 × 3 gives about 115 dpi). A printer that cannot print to the very edge of the paper will shrink the page a little with "fit to page", so trim the white margin from each sheet before you join them edge to edge.

Save formats and file names

• Original format (default): JPG is saved as JPG, PNG as PNG and WebP as WebP. Formats a browser can only open, such as HEIC and AVIF, are saved as JPG if there is no transparency and as PNG if there is.
• PNG: saved without loss and keeps transparency. It suits screenshots with a lot of text and lines, but photos make large files.
• JPG: recompressed at 92% quality. JPG cannot hold transparency, so transparent areas are filled with white.
• WebP: saved at 92% quality and keeps transparency. It cannot be chosen in browsers that cannot create WebP files (such as Safari), and pieces more than 16,383 px on a side cannot be made.

File names are the original name followed by the row and column. Splitting "trip.jpg" 3 × 2 names the first piece trip_r01_c01.jpg and the piece in the first row, second column trip_r01_c02.jpg. The ZIP is built with no compression (storage method 0) and file names are written in UTF-8, because JPG, PNG and WebP are already compressed and compressing them again inside a ZIP barely reduces the size. Pieces are drawn into new files, so EXIF data such as shooting location and camera details is not kept.

Common mistakes

• Posting a square 9-piece split to a profile grid as is: the grid cells are tall, so square pieces get fitted to the cell and the sides of each piece may be hidden. The seams between neighboring pieces then look misaligned, so use 3:4 pieces for a profile grid.
• Splitting a carousel image by Size: splitting by Size makes only the last pieces smaller, so the ratio differs. Every slide in a post gets the same orientation, so the last slide may look cropped differently. Split a carousel by Count.
• Using "Posting order" files in a carousel: Posting order is for profile grids, where number 1 is the bottom-right piece. Added to a carousel in this order, the scene runs backwards.
• Confusing splitting with resizing or cropping: splitting divides every pixel of the original among several files and does not change the size. To make one image smaller, use a resizer; to keep only one part, use a cropper. Only when you set a piece ratio is the outside part cropped.
• Resaving a JPG again and again: each time you split or edit a JPG piece and save it as JPG, it is compressed one more time. Split images with a lot of small text as PNG.

Where is the image processed?

Reading the image, finding blank rows and making the pieces and the ZIP all happen inside this browser. The image and the pieces are not sent to a server, and when you close the page the image you added and the pieces you made are gone. If you upload the saved files somewhere else, that service's own handling applies, and any personal information visible in the image is still visible after splitting, so check it yourself before sharing.

Limits

• One image at a time, opened up to 50 MB and 50 million pixels. Columns and rows are each limited to 32, and the total is limited to 1,024 pieces.
• The canvas size a browser can draw at once differs by browser. iOS devices cannot draw a piece larger than 4,096 × 4,096 in area, so for larger pieces the tool tells you to increase the number of pieces.
• Animated GIF and WebP files are split using their first frame only. HEIC opens only in Safari 17 or later and not in Chrome, Edge or Firefox.
• Snap to blank rows only finds rows that are close to a single color all the way across. On photos, gradients and patterned backgrounds it may not be able to move the cut lines.
• There is no official figure for the exact ratio of Instagram profile grid cells, so the preview uses 3:4. If Instagram changes how it displays them, the real screen may differ.

Basis: the relevant sentences in the documents below were checked on 2026-10-20. The limits of 50 MB, 50 million pixels and 1,024 pieces, and the blank-row threshold (a brightness difference of 12 or less), are values set by this tool.

Sources

• 01Instagram Help — Share multiple photos and videos in one postUp to 20 photos and videos in one post (carousel); the chosen orientation (square, portrait, landscape) applies to every slide
• 02Instagram Help — Photo resolutionAn aspect ratio between 1.91:1 and 3:4 keeps its original resolution, up to 1,080 px wide (566 to 1,440 px tall)
• 03Adam Mosseri — Profile roadmap (Instagram post, 2025-01)Most photos and videos being posted are vertical, so the tall profile grid comes first
• 04W3C — CSS Paged Media Module Level 3: page-sizeA4 is 210 mm × 297 mm, the same as ISO A4 paper
• 05W3C — CSS Values and Units Level 4: Absolute lengths1in = 2.54cm = 25.4mm
• 06ITU-R BT.601Luma weights 0.299, 0.587 and 0.114
• 07PKWARE — .ZIP File Format Specification (APPNOTE.TXT)Compression method 0 = stored with no compression; general purpose flag bit 11 = file names in UTF-8
• 08WHATWG — HTML Living Standard, toBlob()An unsupported type falls back to PNG; quality is 0.0 to 1.0
• 09MDN — <canvas>: Maximum canvas sizeThe maximum size differs by browser, and on iOS devices it is 4,096 × 4,096 pixels
• 10Google for Developers — WebP FAQThe maximum pixel size of a WebP image is 16383 × 16383
• 11MDN — createImageBitmap()imageOrientation defaults to from-image: the image is read rotated according to its EXIF orientation
• 12WebKit — WebKit Features in Safari 17.0Safari 17.0 added support for HEIC images

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