Image Splitter ZIP Order: Read Row and Column Filenames

What the download names mean

A two-dimensional grid uses an _rNcM suffix: N is the row and M is the column, both starting at 1. The part before that suffix is the source filename without its final extension. With PNG output, an input named board.png produces names such as board_r2c3.png. Changing the output format changes the file extension, not the row and column meaning.

A single row or a single column uses a different pattern, such as board_part01.png, board_part02.png, and so on. The grid pattern is used when there is more than one row and more than one column. A missing r and c suffix in a strip export is therefore expected.

These examples describe this site's current naming code. Other image splitter tools can use different conventions. Do not infer a position just because another tool happens to produce a similar filename.

A complete 3 × 4 grid map

Use a source that is 1200 pixels wide and 900 pixels high. Set 3 rows and 4 columns, choose count-based grid splitting, and use PNG output. Since 1200 ÷ 4 = 300 and 900 ÷ 3 = 300, every piece should be 300 × 300. There are 12 pieces, covering 12 × 90,000 = 1,080,000 source pixels.

The table is an independently calculated reconstruction map. Position numbers follow the site's row-first generation loop; the source ranges are inclusive. It is not a claim that your file manager will display those names in the same order.

To reconstruct position 7, read row 2 and column 3 from its name. Put it 600 pixels from the left edge and 300 pixels from the top. The general offsets for this equal-sized example are x = (column − 1) × 300 and y = (row − 1) × 300. These formulas describe placement in a blank 1200 × 900 canvas; they do not add resizing or new space between pieces.

If all 12 files exist but the picture looks scrambled, check their positions before splitting again. Exchanging r2c1 and r1c2 moves correct pixels to the wrong place; it does not mean the original split damaged the image.

Download a numbered fixture to check the ZIP yourself

The small preview below represents a 1200 × 900 PNG with twelve numbered cells. Each cell displays both its row-column label and its expected sequence number. The download is generated on your device, and the instructions isolate one source image so filenames and folders are easy to inspect.

Download board.png

1. Download this fixture, then open the splitter and clear any other queued images.
2. Upload board.png, choose a grid by number of pieces, and enter 3 rows and 4 columns. Use PNG output.
3. Split once and inspect the previews. Each 300 × 300 piece should show one complete cell label.
4. Choose Download all as ZIP for that image and extract the archive.
5. Count 12 PNG pieces. Check that board_r1c1.png shows 1, board_r2c1.png shows 5, and board_r3c4.png shows 12.
6. Reassemble one row at a time using the table. A ZIP viewer's visible sort order is not the reconstruction rule.

The expected checks above come from the fixture layout and the site's naming implementation. They are provided for you to reproduce, not as a recorded measurement of every operating system's archive viewer. If a previous export is already in the download folder, keep this test in a separate extracted folder so older files do not inflate the count.

Why a plain alphabetical sort can put row 10 before row 2

CutMyImage's grid labels use plain row and column numbers, without leading zeroes. A plain character-by-character string sort places board_r10c1.png before board_r2c1.png, because it compares the digit 1 with the digit 2. Some file managers use numeric-aware sorting instead. The behavior of this demonstration is not a promise about which sort mode your file manager uses.

The two lists below sort the same four filenames. The first uses JavaScript's default string sort. The second extracts numeric row and column values, sorts rows numerically, then sorts columns within each row.

board_r10c1.png
board_r10c2.png
board_r2c1.png
board_r2c2.png

board_r2c1.png
board_r2c2.png
board_r10c1.png
board_r10c2.png

For these names, the numeric comparison is (rowA − rowB) || (columnA − columnB). If you build a contact sheet or import sequence, apply that rule to the final _rNcM suffix. Do not parse a digit from somewhere else in the source filename, such as holiday2026. The default string-sort behavior is documented in MDN's Array.sort reference.