Skip to main content

Ceiling and Floor Function Calculator

Find the floor, ceiling, nearest integer, fractional part and distance to each neighboring integer for any decimal, fraction, or named constant (pi, e, phi, √2, √3, √5).

Input

A decimal (-2.75), a fraction (7/3), or a constant: pi, e, phi, sqrt2, sqrt3, sqrt5.

Output

Results
PropertyValue
No data yet
Step-by-Step Solution
Was this helpful?

More ways to use this tool

REST API

curl -X POST https://api.iotools.cloud/v1/tool/ceiling-and-floor-function-calculator \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "value": "7/3"
  }'

Swap in your own key from your account. The tool's fields are the body — no wrapper.

Ask an AI agent

Use the IOTools `ceiling-and-floor-function-calculator` tool (Ceiling and Floor Function Calculator) on this input:

YOUR_INPUT_HERE

Paste this at any agent connected to the IOTools MCP server, then add your input.

Embed widget

<iframe
  src="https://iotools.cloud/embed/ceiling-and-floor-function-calculator/"
  width="100%" height="520" frameborder="0" scrolling="no" loading="lazy"
  title="Ceiling and Floor Function Calculator — iotools.cloud"
  sandbox="allow-scripts allow-forms allow-same-origin allow-downloads allow-popups allow-popups-to-escape-sandbox"
  allow="clipboard-write"
  style="width:100%;border:1px solid #e5e7eb;border-radius:12px;overflow:hidden"></iframe>
<script src="https://iotools.cloud/embed.js" async></script>

Drop this into your own page — free, no key required, just a link back.

Cost per API/MCP callFrom 5 credits
Need more credits?View pricing

Also available with

Guides

The floor function ⌊x⌋ rounds down to the nearest integer; the ceiling function ⌈x⌉ rounds up. This calculator computes both — plus the nearest integer, the fractional part, and how far your value sits from each neighboring integer — for a decimal, a fraction, or a named constant.

Supported inputs

Decimal    -2.75
Fraction   7/3
Constants  pi, e, phi, sqrt2, sqrt3, sqrt5

Worked example: 7/3 ≈ 2.33333 has a floor of 2, a ceiling of 3, and a fractional part of about 0.333333 — the distance up to the ceiling (0.666667) is twice the distance down to the floor.

How it works

Floor ⌊x⌋   = greatest integer ≤ x
Ceiling ⌈x⌉ = smallest integer ≥ x
Fractional part = x − ⌊x⌋           (always between 0 and 1, even for negative x)

For a negative value like -2.75, the floor is -3 (not -2) — floor always rounds down, toward negative infinity, never toward zero.

How to use it

  1. Enter a decimal, a fraction (numerator/denominator), or a constant name.
  2. Floor, ceiling, nearest integer, fractional part, and the distance to each neighboring integer update instantly.

FAQ

Why is the floor of -2.75 equal to -3, not -2? Floor means "round down toward negative infinity," not "drop the decimal part." -3 is less than -2.75, while -2 is greater than it — so -3 is the floor.

What counts as the fractional part of a negative number? It's always x − ⌊x⌋, which stays between 0 and 1 regardless of sign — for -2.75 that's -2.75 − (-3) = 0.25, not -0.75.

Can I enter a negative fraction? Yes — both the numerator and the whole fraction can be negative (e.g. -7/3 or 7/-3).

How is "nearest integer" different from rounding I learned in school? It follows standard rounding (ties round toward positive infinity) — for a value exactly halfway between two integers like 2.5, the nearest integer is 3.

Privacy

Everything runs locally in your browser — the value you enter is never uploaded or stored anywhere.

floor functionceiling functionroundnearest integerfractional partgreatest integer functionfraction to decimalmath

Love the tools? Lose the ads.

One payment clears every ad from your account, for good. No subscription, no tracking.