Screen Time Calculator
See screen time add up.
Formula
Yearly = Hours×Days×52
Example
6h/day → 2,184h/year (91 days).
Understanding the Screen Time
Design calculators handle the math that turns creative intent into production-ready specs - pixel densities, paper weights, aspect ratios, file sizes. The screen time calculator gives you the technical answer for design decisions where intuition is not enough.
How it actually works
See screen time add up.
The formula is straightforward arithmetic once the inputs are correct; the value of the calculator is in handling the algebraic manipulation reliably and removing transcription errors. Plug in your specific inputs above and the result appears as you type, so you can immediately see how each variable affects the answer.
What the numbers really say
A 4x6 inch print at 300 DPI requires 1200x1800 pixels - far more than most phone screenshots provide. Same image at 72 DPI is fine for web display but pixelates badly when printed. Web vs print resolution requirements differ by ~4x; designing once for both means designing at print resolution.
The deeper context most users miss
Design calculator output sits at the boundary between technical precision and human perception. A 300 DPI print specification is mathematically precise but the human eye cannot distinguish print quality above about 240 DPI at typical viewing distance. The calculator can tell you to print at higher resolution; whether the additional precision is worth the file size and processing cost depends on the actual viewing context. Print designers have internalized these perceptual thresholds; calculator output is the technical starting point that gets adjusted for actual production constraints.
What people get wrong
- Confusing physical with pixel dimensions. A 4x6 photo at 300 DPI is 1200x1800 pixels - both numbers matter for different reasons.
- Designing screens at print resolution. Web pages do not benefit from 300 DPI; it just inflates file size.
- Forgetting bleed and trim margins. Designs that touch the edge need to extend beyond the trim line.
- Mixing color spaces. RGB for screens, CMYK for print - same color values mean different things.
When this calculator helps most
The screen time calculator is most useful when you are making a real decision - comparing options, sizing a commitment, sanity-checking a quote, or planning ahead. The output is precise to your inputs; the inputs themselves are the place to slow down. Spend extra time on the assumptions you are making about rate, term, timing, or context-specific variables - those swing the answer far more than the formula's arithmetic does. A 5% change in the input often produces a 10-20% change in the output, which means small input errors compound into large output errors.
Where the math comes from
Adobe's color management documentation. ISO 216 specifies international paper sizes (A-series). The W3C specifies web-relevant standards (CSS pixel definitions, viewport metadata). Print industry standards from the GASP (Graphic Arts Show Producers) and PIA (Printing Industries of America).
Questions and answers
DPI vs PPI?
DPI (dots per inch) is print resolution. PPI (pixels per inch) is screen/file resolution. Often used interchangeably in casual usage.
What resolution for web vs print?
Web: 72-96 PPI is typical; high-DPI displays may serve 2x. Print: 300 DPI for photos, 600+ for line art and small text.
RGB or CMYK?
RGB for screens (additive color, light). CMYK for print (subtractive, inks). Color conversion between them is lossy; design in the destination color space when possible.
What is bleed?
Print area extending past the trim line so cut artwork has no white edges from imperfect cutting. Standard bleed is 0.125 inch (3mm) all around.
How big should source images be?
Always work at the largest size and resolution you might need, then export down. Going up rarely works.
Related calculators
DPI Image · Screen DPI · Paper Size · GSM Paper Weight · Aspect Ratio