Calculators
Planning tools related to creative everyday living, with visible assumptions and clearly explained results.
Calculate a person's age at death from their birth date and date of death. Enter both dates as years, months, and days to estimate elapsed age using a transparent 365-day year and 30-day month convention.
Find the absolute difference between two ages in years. Enter both ages using the same unit and compare the result as a simple age gap.
Estimate the number of boxes needed for an archive by dividing the document count by the number of documents each box holds, then adding spare boxes. The result is rounded up to a whole box.
Estimate the total shelf length needed for archive boxes by multiplying the number of boxes by the box width plus the clearance allocated per box. Enter all measurements in meters.
Estimate an art commission price from your hourly rate, work time, material cost, and revision allowance. The estimate assumes all entered time is billable and does not include taxes, shipping, or platform fees.
Estimate the amounts of two paints or pigments needed to make a color blend using a simple proportional mixture model. Enter each starting color's red, green, and blue values from 0 to 255, then choose the blend percentage contributed by Color A.
Calculate a camera sensor's crop factor and the equivalent full-frame focal length from sensor width and lens focal length. This width-based estimate assumes a 36 mm full-frame reference.
Estimate a birth year from a person's age in completed years and the year when that age was recorded. This simple subtraction is useful for organizing genealogy notes and archive searches; it does not establish an exact birth date.
Convert a real-world length to its corresponding drawing length, or convert a drawing length back to the real-world measurement, using a scale ratio.
Convert a lens’s actual focal length to its 35mm-equivalent focal length using the camera sensor’s crop factor.
Convert an exposure compensation value in stops (EV) into a relative exposure multiplier. Positive values increase exposure and negative values reduce it. The result does not select camera settings.
Calculate the exposure value (EV) of a camera setting from aperture and shutter speed, using EV = log₂(f-number² ÷ exposure time in seconds). This result describes the setting's exposure value and does not account for ISO.
Estimate fabric yardage for rectangular projects by adding measured panel areas and an allowance for cutting waste. This estimate assumes fabric is usable across its full width and does not account for pattern matching, nap, seams, or layout constraints.
Estimate the number of boxes needed for a family archive by dividing the total number of documents by the number each box can hold. The estimate assumes documents are counted consistently and packed to the selected capacity.
Estimate the total cost of labeling family archive boxes by multiplying the number of boxes by labels per box and cost per label. This estimate assumes every box uses the same number of labels and each label has the same unit cost.
Estimate the horizontal scene width covered at a given subject distance using sensor width and focal length.
Calculate the approximate flash-to-subject distance from a flash guide number and the selected camera aperture. The guide number and distance use the same units, and the result assumes the guide number applies to the flash setup in use.
Calculate a lens focal length from image magnification and subject distance, using the thin-lens approximation. Enter both distances in the same units.
Estimate a frame's outside dimensions from the artwork size, mat borders, and frame width. This is a dimensional planning estimate and does not account for rabbet depth, glazing, or fitting tolerances.
Multiply a known length by an approximation of the golden ratio to find the corresponding longer length in the same unit.
Estimate the hyperfocal distance from focal length, f-number, and circle of confusion. The result uses the conventional formula H = f²/(N × c) + f and is expressed in the same units as focal length and circle of confusion.
Calculate an image's aspect ratio from its width and height, or find a proportional dimension when one side is resized. Enter the image dimensions in pixels.
Estimate an image file's uncompressed pixel data size from its dimensions and color depth. The estimate excludes file-format compression and metadata.
Calculate new image dimensions while preserving the original aspect ratio. Enter the source width and height, then set the target width or height to find the matching dimension.
Estimate the Airy disk diameter and diffraction-limited image detail for a given aperture, wavelength, and magnification. The model uses the Rayleigh criterion for a circular aperture and reports the Airy disk diameter at the sensor plane.
Calculate image-side macro magnification from the subject size and its image size on the sensor. Enter both measurements in the same units. This simple ratio does not account for cropping or lens markings.
Estimate how many photos or videos a memory card can hold from its labeled capacity, the space available for files, and the average size of each file. Results are approximate and use decimal gigabytes.
Estimate a painting project's price from paintable area, labor time, hourly rate, materials per area, and a project complexity factor.
Estimate a panorama print's width from its pixel dimensions and the desired print height. The calculation assumes the image keeps its original aspect ratio, with no cropping or distortion.
Estimate the label-material cost for a photo archive by multiplying the number of boxes by the labels used per box and the price per label. This estimate assumes every box uses the same number of labels and every label has the same unit price.
Estimate the storage capacity in gigabytes needed for a photo archive based on the number of photos, average file size, and number of copies kept.
Estimate the total layout area for a photo collage using the number of photos, each photo's width and height, and the gap added to both dimensions. The calculation treats every photo as a same-sized square layout cell.
Estimate the pixel dimensions and total pixel area of a photo contact sheet from its column count, row count, thumbnail dimensions, and uniform gutter. The calculation assumes thumbnails retain the entered dimensions and uses the gutter only between neighboring thumbnails, with no outer margins.
Estimate the pixel dimensions and print size of an enlarged photo from its original pixel dimensions and chosen print resolution. The calculation assumes the image is scaled proportionally without cropping.
Calculate the height of a photo print that preserves the original image's aspect ratio when you choose a print width.
Estimate a photo's print width or height from its pixel dimensions and a selected print resolution. The calculation converts pixels to inches using pixels per inch (PPI).
Estimate the storage capacity needed for a photo collection from photo count, average file size, RAW share, and a capacity reserve. This is a planning estimate based on the file sizes you enter.
Estimate the finished outside dimensions of a picture mat from the artwork opening and border reveal. This arithmetic guide assumes equal borders on all four sides and does not account for frame rabbet, overlap, or cutting tolerances.
Calculate pixel density in pixels per inch (PPI) from a display's pixel dimensions and diagonal size.
Convert a pixel measurement to centimeters using a selected pixels-per-inch (PPI) density. Enter the pixel count and the resolution used by your design or display.
Convert a pixel measurement to inches using the pixels-per-inch (PPI) value of the image or display. Enter the pixel count and PPI to calculate the corresponding physical length.
Estimate the uncompressed storage size of a raw image from its pixel dimensions, bit depth, color channels, and an assumed compression ratio.
Convert red, green, and blue channel values from 0 to 255 into a six-digit hexadecimal color code.
Calculate a scaled measurement by multiplying an original length by a scale factor. Use a factor below 1 to reduce a design and a factor above 1 to enlarge it.
Estimate the total adhesive units needed for a scrapbook by multiplying the number of pages by the adhesive units you plan to use per page.
Estimate the number of scrapbook pages needed for a photo collection by dividing photos by photos per page and adding any pages reserved for notes or other written material.
Estimate how many sheets of scrapbook paper you need from your page count, sheets planned per page, and spare sheets. The estimate assumes each planned sheet is used once and spares are added to the total.
Compare two camera sensor sizes by calculating their diagonal measurements and the crop factor between them. Enter each sensor's width and height in millimeters.
Calculate an equivalent shutter speed when you change aperture or ISO, using the exposure triangle and assuming the scene brightness stays constant.
Estimate the number of seconds between photographs from your planned capture duration, target video length, and playback frame rate.