THE NUMBERS, EXPLAINED
How to use this calculator.
Initial image indices are unique. The scenario loads the stated fraction of remaining images in page order, rounding the number upward. It estimates transferred image bytes, not browser behavior, network time or actual user scroll patterns.
Start with your inputs
Enter image byte sizes in page order, initially loaded image numbers (1-based), remaining images reached by scrolling (%). Keep amounts in the units shown on each field. The example is a starting point, not a recommended value.
| Input | Example value |
|---|---|
| Image byte sizes in page order | 100,200,300,400 |
| Initially loaded image numbers (1-based) | 1,2 |
| Remaining images reached by scrolling (%) | 50 |
A worked example
With the example inputs above, initial image bytes is 300. Change the inputs to explore your own scenario.
| Result | Example answer |
|---|---|
| Initial image bytes | 300 |
| Scenario total image bytes | 600 |
| Eager-load image bytes | 1,000 |
| Scenario bytes saved | 400 |
How this is calculated
Initial image bytes
Sum sizes at the initially loaded indices.
Scenario total image bytes
Add the first roundUp(remaining count × scroll percentage/100) remaining images to initial bytes.
Eager-load image bytes
Sum all image byte sizes.
Scenario bytes saved
Eager-load bytes minus scenario total.
Symbols and units
- a
- Image byte sizes in page order
- b
- Initially loaded image numbers (1-based)
- c
- Remaining images reached by scrolling (%)
Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.
Assumptions and limits
Initial image indices are unique. The scenario loads the stated fraction of remaining images in page order, rounding the number upward. It estimates transferred image bytes, not browser behavior, network time or actual user scroll patterns.
Calculations use the values you enter. Blank or invalid inputs show an error instead of silently substituting zero. Results are displayed to useful precision; calculations retain the underlying numeric precision.
Questions about this tool
What does the result tell me?
Initial image bytes; Scenario total image bytes; Eager-load image bytes; Scenario bytes saved. The result applies to the method and inputs described above. Check the units and assumptions before using it in a decision.
Why might another calculator differ?
Differences in units, rounding, timing or model definitions can produce different answers. Compare the input definitions and the method, rather than only the final number. For this tool: Initial image indices are unique. The scenario loads the stated fraction of remaining images in page order, rounding the number upward. It estimates transferred image bytes, not browser behavior, network time or actual user scroll patterns.
Are my inputs stored or sent to AI?
Calculations on this page happen in your browser. The separate AI question finder sends its submitted conversation to OpenAI; these calculator fields are not sent. Favourites and recent tool names are stored locally. A shared link contains the inputs you choose to include.
Further reading
OpenStax: percentages and proportions ↗
Background reading; this does not imply endorsement or independent review of SumFizz.
Review status
Software example and browser checks are recorded in our quality report. No external expert review is claimed. Created with coding assistance; calculations run as ordinary browser code.
Read the quality report →