Mathematics · Statistics
F1 Harmonic Classification Score Calculator
Calculate f1 score from positive predictive value and sensitivity or recall.
Inputs and results stay in this browser. Change one value at a time to explore the relationship.
Calculation steps
- Use c=2ab/(a+b) with positive predictive value=0.86 and sensitivity or recall=0.92.
- F1 score=0.8889887640449439.
Understand F1 Harmonic Classification Score
One idea, three depths
Choose how deeply to explain F1 Harmonic Classification Score
F1 Harmonic Classification Score: Calculate f1 score from positive predictive value and sensitivity or recall.
Age 5Explain it to a 5-year-oldStart with a picture
Imagine using F1 Harmonic Classification Score to answer this question: calculate f1 score from positive predictive value and sensitivity or recall? Enter positive predictive value and sensitivity or recall; the calculator shows F1 score. For example: positive predictive value=0.86 and sensitivity or recall=0.92 produce F1 score=0.8889887640449439. The answer tells you F1 score.
Age 15Explain it to a 15-year-oldConnect it to the formula
The F1 score is the harmonic mean of positive predictive value and recall. This page evaluates the relationship directly. The rule is c=2ab/(a+b). Its input values are positive predictive value, sensitivity or recall, and the main result is F1 score. For example: positive predictive value=0.86 and sensitivity or recall=0.92 produce F1 score=0.8889887640449439.
CollegeExplain it at college levelState the model precisely
This calculator evaluates the stated f1 harmonic classification score relation over the valid real-number domain stated below. The implemented relation is c=2ab/(a+b), evaluated from positive predictive value, sensitivity or recall to produce F1 score. The F1 score is the harmonic mean of positive predictive value and recall. This page evaluates the relationship directly. Use consistent decimal or percentage scales for both inputs and remember that true negatives do not enter F1.
Inputs and valid domain
- positive predictive value must be a finite real number.
- sensitivity or recall must be a finite real number.
Important boundary: Use consistent decimal or percentage scales for both inputs and remember that true negatives do not enter F1.
The formula
c=2ab/(a+b)
How the calculator works through it
It substitutes positive predictive value, sensitivity or recall into the formula and exposes every numerical step above. The main output is F1 score.
Read the result correctly
The F1 score is the direct answer to “calculate f1 score from positive predictive value and sensitivity or recall.” Read it with the units shown beside the inputs; a sign, angle, percentage or rate changes what the number means.
A worked check
positive predictive value=0.86 and sensitivity or recall=0.92 produce F1 score=0.8889887640449439.
Where this model stops being reliable
Use consistent decimal or percentage scales for both inputs and remember that true negatives do not enter F1.
Learn it by changing one value
Begin with the worked example, then change one value while keeping the others fixed. Compare the new result and calculation steps to identify which part of the formula changed.
Dictionary terms behind this calculator
Before studying the codeWhat you should know firstUse the calculator immediately, or check the foundations before reading the implementation.
These foundations help you understand why F1 Harmonic Classification Score works. They never block the calculator, and “optional” means useful context rather than a hidden requirement.
Hard requirements
- Reading formulas and substituting values
F1 Harmonic Classification Score uses c=2ab/(a+b). You need to recognise what each side represents before substituting the stated inputs or rearranging the relationship.
Review this foundation about 4 min
Strong support
- Averages and representative values
Representative values help you judge what the F1 Harmonic Classification Score inputs summarise and what the result can legitimately describe.
Review this foundation about 5 min
Optional enrichment
- Spread and measurement variation
Variation is not always part of the F1 Harmonic Classification Score formula, but it helps you judge how stable a reported result may be.
Review this foundation about 6 min
Mathematics → algorithm → program
Implement this calculation in code
These are direct reference implementations of the calculator's principal relationship and first output. They run locally and include a small known-answer check where the language supports it.
Algorithm
- Read positive predictive value, sensitivity or recall.
- Evaluate the principal relationship: c=2ab/(a+b).
- Return F1 score and check the domain conditions described above.
Python
from math import *
def f1_harmonic_score_calculator(a, b) -> float:
return ((2.0 * (a * b)) / (a + b))
assert abs(f1_harmonic_score_calculator(0.86, 0.92) - 0.8889887640449439) < 1e-6 * max(1.0, abs(0.8889887640449439))
C
#include <assert.h>
#include <math.h>
double f1_harmonic_score_calculator(double a, double b) {
return ((2.0 * (a * b)) / (a + b));
}
int main(void) {
const double expected = 0.8889887640449439;
const double actual = f1_harmonic_score_calculator(0.86, 0.92);
assert(fabs(actual - expected) < 1e-6 * fmax(1.0, fabs(expected)));
}
C++
#include <cassert>
#include <cmath>
#include <numbers>
double f1_harmonic_score_calculator(double a, double b) {
return ((2.0 * (a * b)) / (a + b));
}
int main() {
constexpr double expected = 0.8889887640449439;
const double actual = f1_harmonic_score_calculator(0.86, 0.92);
assert(std::fabs(actual - expected) < 1e-6 * std::fmax(1.0, std::fabs(expected)));
}
Linux x86-64 assembly
x86-64 NASM · System V ABI · Linux · SSE2 with libm where required
; double f1_harmonic_score_calculator(double a, double b)
; Linux x86-64 NASM · System V ABI · first eight doubles in xmm0–xmm7
global f1_harmonic_score_calculator
section .text
f1_harmonic_score_calculator:
push rbp
mov rbp, rsp
sub rsp, 64
movsd [rbp-8], xmm0
movsd [rbp-16], xmm1
mov rax, 0x4000000000000000
movq xmm0, rax
movsd [rbp-40], xmm0
movsd xmm0, [rbp-8]
mulsd xmm0, [rbp-16]
movsd [rbp-48], xmm0
movsd xmm0, [rbp-40]
mulsd xmm0, [rbp-48]
movsd [rbp-32], xmm0
movsd xmm0, [rbp-8]
addsd xmm0, [rbp-16]
movsd [rbp-56], xmm0
movsd xmm0, [rbp-32]
divsd xmm0, [rbp-56]
movsd [rbp-24], xmm0
movsd xmm0, [rbp-24]
leave
ret
MATLAB
function result = f1_harmonic_score_calculator(a, b)
result = ((2.0 * (a * b)) / (a + b));
end
Wolfram Language
ClearAll[mwCalculate];
mwCalculate[a_, b_] := ((2.0 * (a * b)) / (a + b));
Continue in mathematical software
The downloaded file includes your current inputs and first calculated result. It is created locally.
Floating-point answers can differ slightly by language, compiler and processor. Compare within a suitable tolerance rather than assuming every decimal representation will be identical.
Supporting sourcesAcademic referencesPrimary standards, textbooks and complete citations
Standards, reading and academic references
Use the calculator as the worked interaction, then consult the primary standards and academic textbooks listed below. MW SysArc links to the original sources; the explanation on this page is original and does not reproduce them.
Introductory Statistics 2e
Read the free OpenStax statistics textbookCite this book
- APA 7
- Illowsky, B., & Dean, S. (2023). Introductory statistics 2e. OpenStax. https://openstax.org/books/introductory-statistics-2e/pages/1-introduction
- MLA 9
- Illowsky, Barbara, and Susan Dean. Introductory Statistics 2e. OpenStax, 2023, https://openstax.org/books/introductory-statistics-2e/pages/1-introduction.
- Chicago author-date
- Illowsky, Barbara, and Susan Dean. 2023. Introductory Statistics 2e. Houston, TX: OpenStax. https://openstax.org/books/introductory-statistics-2e/pages/1-introduction.
OpenStax entries are free to read online. Follow the licence shown on each linked source before redistributing or adapting its content.
Reuse the page responsiblyCite this pageAPA, MLA, Chicago, Harvard, BibTeX and RIS
These formats cite this calculator page itself. They are separate from the academic references above, which support the mathematical method and terminology.
APA 7
MW SysArc. (2026, July 21). F1 Harmonic Classification Score Calculator. MW SysArc Tools. https://math.mwsysarc.com/statistics/f1-harmonic-score-calculator
MLA 9
MW SysArc. “F1 Harmonic Classification Score Calculator.” MW SysArc Tools, 21 July 2026, https://math.mwsysarc.com/statistics/f1-harmonic-score-calculator. Accessed 31 Aug. 2026.
Chicago 17
MW SysArc. “F1 Harmonic Classification Score Calculator.” MW SysArc Tools. Published July 21, 2026. Accessed August 31, 2026. https://math.mwsysarc.com/statistics/f1-harmonic-score-calculator.
Harvard
MW SysArc (2026) ‘F1 Harmonic Classification Score Calculator’, MW SysArc Tools. Published 21 July 2026. Available at: https://math.mwsysarc.com/statistics/f1-harmonic-score-calculator (Accessed: 31 August 2026).
BibTeX and RIS records
BibTeX
@misc{mwsysarc_f1_harmonic_score_calculator_2026,
author = {{MW SysArc}},
title = {F1 Harmonic Classification Score Calculator},
howpublished = {MW SysArc Tools},
year = {2026},
url = {https://math.mwsysarc.com/statistics/f1-harmonic-score-calculator},
note = {Published July 21, 2026; accessed August 31, 2026}
}RIS
TY - ELEC
AU - MW SysArc
TI - F1 Harmonic Classification Score Calculator
T2 - MW SysArc Tools
PY - 2026
DA - 2026-07-21
Y2 - 2026-08-31
UR - https://math.mwsysarc.com/statistics/f1-harmonic-score-calculator
N1 - Published July 21, 2026
ER -Clear answers
Frequently asked questions
What does the F1 Harmonic Classification Score do?
Calculate f1 score from positive predictive value and sensitivity or recall.
How does the F1 Harmonic Classification Score work?
The calculator applies c=2ab/(a+b). The F1 score is the harmonic mean of positive predictive value and recall. This page evaluates the relationship directly.
What can I learn from the F1 Harmonic Classification Score?
It connects the mathematical rule to your chosen numbers and shows each calculation step. Change one input at a time to see how the result responds.
Does MW SysArc receive or store what I enter?
No. The calculation runs locally in your browser. MW SysArc does not receive or store your calculation inputs.
How should I use the result?
Use the steps to understand the method, then verify important school or professional work using the notation and rounding rules required in your setting.
Last reviewed . Calculations tested .