Conversion assay / instrument-grade

Convexa is a free websiteconversion optimization toolthat grades any URL.

Paste any homepage and Convexa runs a calibrated conversion assay, the way a bench instrument measures a part against spec. It reads five things that decide whether a visitor acts: the clarity of your call to action, whether your offer lands above the fold, how much friction sits between intent and click, the trust signals on the page, and load speed. Each axis is scored from 0 to 100, weighted, and settled into one composite grade with a prioritized list of fixes. No signup, no install, no dashboard to learn. Most tools tell you what happened. Convexa tells you what to fix first, and why it is costing you conversions.

Or load a specimen:

Composite conversion gradeReady
62
C+

Composite conversion score 62 of 100, grade C plus.

Solid trust signals, but the offer is working too hard above the fold. Sharpen the primary call to action first.

Plate 01What it measuresUnit: pts

Five axes decide whether a visitor converts.

Convexa does not grade taste. It grades the five things that move a conversion rate, the same factors a studio checks before it ships a page. Each axis is scored independently from 0 to 100, then weighted by how much it actually swings outcomes, so a beautiful page with a buried call to action still reads as a low grade. The weights are fixed and public, listed in the right-hand column, so the composite is reproducible rather than a matter of opinion. Read the legend as the specification sheet for the instrument: this is exactly what the needle responds to, and nothing else.

Plate 02Measurement procedureMethod

How the conversion score is calculated.

The composite is a weighted mean of the five axes: CTA clarity counts for 25 points, the above-the-fold offer for 25, friction for 20, trust signals for 15, and load speed for 15. Each axis is scored from 0 to 100, combined into a single 0 to 100 composite, and mapped to a letter grade where 90 and up is an A, 80 a B, 70 a C, 60 a D, and anything lower an F. The same URL always returns the same reading, because the score is deterministic rather than sampled. Convexa is a demonstration grader: it scores from the URL and public signals, not from your analytics.

composite = (CTA×25 + Offer×25 + Friction×20 + Trust×15 + Speed×15) / 100

  1. Load the specimen. Paste any URL into the load tray and run the audit. Nothing is stored, and there is no account.
  2. The instrument probes six signals. Above-the-fold capture, CTA hierarchy, friction index, trust scan, a speed proxy, and host resolution all read in sequence.
  3. Read the grade and the fix list. The needle settles on a composite, each axis returns a plain-English finding, and the fixes are ordered by impact, lowest axis first.
Plate 03Calibration certificateCompare

A reading beats an opinion.

Most teams audit conversions one of three ways. Two of them are guesses.

Conversion diagnosis, by method
CapabilityEyeballing itGeneric CRO checklistConvexa
Objective 0 to 100 scoreNoNoYes
Five-axis breakdownNoPartialYes
Plain-English fixesMaybeNoYes
Repeatable resultNoYesYes
Prioritized by impactNoNoYes
PriceFreeFreeFree
Plate 04SpecificationsProbes

What the instrument actually checks.

Each probe is narrow on purpose. A conversion grader earns trust by measuring concrete, observable things and reporting them in units, not by hand-waving about best practices. These are the five readings the composite is built from, and the order Convexa fixes them in.

Probe 01 / weight 25

CTA hierarchy

Counts the competing calls to action above the fold and scores how clearly the single primary action stands apart from everything else on the page.

RANGE 0-100 pts / TOL +/-3
Probe 02 / weight 25

Above-the-fold offer

Reads whether the value proposition and the offer are legible before any scroll, in the first five seconds.

RANGE 0-100 pts
Probe 03 / weight 20

Friction index

Estimates the steps, fields, and decisions between intent and the click that completes the action.

RANGE 0-100 pts
Probe 04 / weight 15

Trust scan

Looks for the proof a buyer needs: secure transport, social proof, and credible specifics over adjectives.

RANGE 0-100 pts
Probe 05 / weight 15

Speed proxy

Approximates load behavior, since a page that arrives late converts late, or not at all.

RANGE 0-100 pts
Plate 05Frequently measuredFAQ

Questions, answered.

Q.01

Is Convexa free to use?

Yes. Convexa is free, with no signup and no install. It is a demonstration grader you can run on any URL to see how its conversion design holds up.

Q.02

How does the Convexa conversion score work?

The score is a weighted mean of five axes: CTA clarity 25, offer 25, friction 20, trust 15, and speed 15. Each is scored 0 to 100 and mapped to one composite grade. The same URL always returns the same reading.

Q.03

How is a conversion grader different from analytics?

Analytics tells you what visitors did. A grader diagnoses why a page underperforms and ranks the fixes by impact, before you have enough traffic to A/B test.

Q.04

I have my score. What should I do with it?

The score is a diagnosis, not a cure. Fix the lowest axis first. Shape Meets Form rebuilds your highest-leverage page to score in the 90s.