Image File Size Calculator - Uncompressed Raster Size in MB

An image file size calculator turns width, height, and bit depth into the uncompressed file size of a raster image in bits, bytes, kilobytes, megabytes, and gigabytes. This image file size calculator is built for any uncompressed raster format, not for compressed JPEG or PNG.

• • Plan storage for RAW or uncompressed exports: Estimate how many megabytes each frame costs on the memory card before compression.
• • Estimate upload and download time: Pair the file size in MB with the data-transfer calculator for transfer durations.
• • Compare bit depth choices: Switch between 8-bit grayscale, 24-bit RGB, and 48-bit deep color at fixed pixel count.
• • Verify a vendor's image size claim: Use it to check a printed spec or contract without opening a graphics editor.

This calculator is built around the raster model: every digital photo is a rectangular grid of pixels, each carrying a fixed number of bits. Multiplying pixel count by bit depth gives the raw file size in bits.

It works for any uncompressed raster format such as BMP, RAW, or uncompressed TIFF. For JPEG, PNG, WebP, or AVIF, the file on disk will be smaller than the value the calculator returns; that number is the ceiling that compression squeezes down toward.

When the KB, MB, or GB value needs to switch between SI decimal prefixes (1,000 bytes per KB) and binary prefixes (1,024 bytes per KiB), the Data Storage Converter in the same Tools category converts the size into KiB, MiB, or GiB without a separate unit table.

Internally the calculator multiplies width by height to get the pixel count, multiplies that by the bit depth to get the file size in bits, and then divides by 8 and by 1000 to walk the SI decimal byte ladder down to bytes, kilobytes, megabytes, and gigabytes.

• width: Image width in pixels (640, 1920, 3840).
• height: Image height in pixels (480, 1080, 2160).
• bit_depth: Bits per pixel. 1 for monochrome, 8 for grayscale, 24 for RGB, 48 for deep color.
• pixel_count: Total pixels, equal to width x height. Scales file size linearly.
• file_size_bits: Uncompressed bits; divide by 8 for bytes, then 1000 for KB.
• resolution (DPI): Optional print context; DPI does not change the bit-level file size.

Wikipedia's raster graphics article defines a raster image as a rectangular grid of pixels and gives the same pixel count x bit depth identity as the file size in bits. The byte ladder uses the SI decimal system (1 KB = 1000 bytes) that Wikipedia attributes to the IEC 80000-13 standard.

According to Wikipedia (Raster graphics), a raster image is stored as a rectangular grid of pixels, and the uncompressed file size is the pixel count multiplied by the bit depth in bits per pixel

According to Wikipedia (Bit depth), color depth or bit depth is the number of bits used to indicate the color of a single pixel, and a 24-bit image can represent up to 2^24 = 16,777,216 colors

To turn the uncompressed MB value from this calculator into a transfer time at a given bandwidth, the Data Transfer Calculator in Tools reads the file size alongside an upload or download throughput and returns the duration.

Four ideas are enough to read every number the calculator shows: pixel count, bit depth, the SI decimal byte ladder, and the difference between compressed and uncompressed storage.

These four ideas turn the result table into a chain of consequences rather than a wall of numbers. Once pixel count and bit depth are set, every other row follows from the same two inputs.

Bit depth and pixel count set the ceiling on every digital image, and the Upload Time Calculator in Tools converts that ceiling into the upload time you would actually see at a given Mbps connection.

Four steps cover every workflow this calculator supports, from a one-off sanity check to a storage plan for a whole shoot.

1. 1 Type the image width and height in pixels: Pull these from your camera's spec sheet, your photo editor's export dialog, or your OS image properties window.
2. 2 Pick the bit depth: 1-bit for monochrome, 8-bit for grayscale or 256-color, 24-bit for standard RGB photos, 48-bit for deep color, 32-bit for CMYK print separations.
3. 3 Optionally set the print DPI: DPI does not change the bit-level file size, but it lets you read print dimensions at the same time.
4. 4 Read the uncompressed file size in all four units: Bits, bytes, KB, MB, and GB side by side, plus the total pixel count and effective megapixels.

For a Full HD 1920 x 1080 photo at 24-bit RGB, set width = 1920, height = 1080, bit depth = 24. The calculator returns 2,073,600 pixels, 6,220,800 bytes, and 6.2208 MB.

For a sequence of frames, the Time Lapse Calculator in Tools estimates total photos, clip length, and storage budget for the same pixel dimensions.

This calculator removes the spreadsheet work, lines the four byte units up in one view, and pairs naturally with the storage and bandwidth calculators that turn file size into a real-world plan.

• • All four byte units in one view: Bits, bytes, KB, MB, and GB appear on the same screen, so you can copy whichever unit matches the spec sheet or bandwidth calculator you are using.
• • Direct link to bandwidth and upload planning: Pair the MB row with the upload-time calculator to turn file size into an upload duration at a given Mbps connection.
• • Built-in validation for out-of-range inputs: If width, height, or bit depth fall outside the supported range, the calculator surfaces a clear validation error instead of producing an undefined byte count.
• • Print DPI context without changing the math: DPI is excluded from the file-size math, so a 300 DPI export and a 72 DPI export of the same pixel grid report the same bit count.
• • Matches the Omni Calculator worked example: The default 1920 x 1080 at 24-bit preset reproduces the 6.2208 MB Full HD ceiling; the 640 x 480 preset reproduces the 921.6 KB Omni Calculator example.

If you need to convert the resulting size into different storage prefixes (such as MiB or GiB), the data-storage-converter in the same Tools category handles the SI/binary switch in one click.

If you need to verify that an exported image has not changed, paste the resulting MD5 or SHA-256 hex digest into the Hash Identifier Calculator in Tools to recognise whether the hex string is an MD5, SHA-1, SHA-256, or other fingerprint by its length.

Three things change the resulting file size, plus two caveats about compressed formats and float precision.

• • This calculator covers uncompressed raster bitmaps only. Vector formats such as SVG and PDF store equations instead of pixels, so their file size depends on path complexity.
• • The bit depth options match the standard RGB, CMYK, grayscale, and deep-color pipelines. Specialized pipelines such as 10-bit Rec. 2020 video or 16-bit float HDR may need a custom bit depth outside the preset list.

When you copy a row from the result table into another calculator, watch the units: bits, bytes, KB, MB, and GB are different powers of 8 and 1000. If the next calculator expects bytes, use the bytes row; mixing units is the most common source of off-by-1000 errors in image-storage math.

If the file size you are comparing came from a JPEG or PNG that already exists on disk, the calculator's value will be larger than the actual file. The gap is the compression ratio; if your compressed file is 1 MB and the calculator says 6.22 MB, the encoder reached about a 6:1 ratio.

According to Wikipedia (Kilobyte), the SI decimal system used by storage manufacturers and the IEC 80000-13 standard defines 1 kilobyte as 1000 bytes, 1 megabyte as 1000 kilobytes, and 1 gigabyte as 1000 megabytes

Pixel count, which this calculator multiplies by bit depth to produce the file size, also drives landscape focus depth, and the Hyperfocal Distance Calculator in Tools uses the same sensor and focal-length inputs to compute the hyperfocal distance for the same kind of shot.