Snipget.ai

Numbers math pct change

Exact
numbers_math_pct_change

Deterministic and authoritative — the canonical answer for this input.

Return (new - old) / old as a fraction plus display string. Negative when decreasing. Rejects old=0.

Parameters

oldnumberrequired
newnumberrequired

Call it

curl -X POST https://api.snipget.ai/v1/numbers/math/pct-change \
  -H "Authorization: Bearer sk_live_..." \
  -H "Content-Type: application/json" \
  -d '{"old":100,"new":120}'

Example response

{
  "fraction": 0.2,
  "display": "20.00%",
  "old": 100,
  "new": 120
}

FAQ

What does percent change tell me?

It measures how much a value moved from a starting point to an ending point, as a share of the start. Going from 100 to 120 is a 20% increase; going from 120 to 100 is about a 17% decrease. It is directional, so the order matters.

How is this different from percent difference?

Percent change has a clear before and after (old then new) and can be negative. Percent difference is order-independent and compares two values with no notion of which came first. Use change for growth or trends over time, difference for comparing two measurements.

Does it handle decreases?

Yes. A drop returns a negative fraction, for example old 120 to new 100 gives roughly -0.17, shown as '-16.67%'.

Is the result exact?

Yes, it is a deterministic calculation. The fraction is returned in full precision and a two-decimal display string is included for convenience.

What if the old value is zero?

Percent change is undefined when the starting value is zero, so you get a result flagged is_valid false with a why_invalid reason and confidence 0, not an error.

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