Catch hERG and CYP liabilities before your first assay.

Calibrated ADMET predictions that flag when your chemistry is too novel to trust — built on ADMET-AI, honest about uncertainty.

4 safety targets Results in seconds (CPU) Built on ADMET-AI
Built on open science, honest about uncertainty CYP AUROC 0.94–0.95 in-distribution Applicability-domain abstention Built on ADMET-AI Zero mock data

Benchmarks

Measured on novel chemistry — and published in full

Every headline here survives an independent, de-leaked test. Where the model can’t stand behind a number, we say so — and the product abstains instead of guessing.

What calibration buys you — hERG on de-leaked novel chemistry
0.5 0.7 0.8 screen 0.9 0.71 0.84 +0.13 AUROC ADMET-AI ToxScreen

On de-leaked novel chemistry — a Karim cross-dataset holdout with every InChIKey overlap removed — the calibrated ToxScreen pipeline (applicability-domain re-weighting + isotonic calibration) lifts hERG discrimination from the raw ADMET-AI baseline 0.71 to 0.84 AUROC, clearing the 0.8 screening bar. Just as important, it fixes the model’s confidence: expected calibration error drops from 0.32 to 0.08.

3-seed mean ± 0.02 SD. hERG is the one endpoint with a genuine novel-chemistry number; the full per-endpoint de-leak — including where we fail — is detailed below.

+0.13 AUROC
hERG lift on novel chemistry
ADMET-AI 0.71 → ToxScreen 0.84, de-leaked (Karim cross-dataset, InChIKey-filtered).
0.32 → 0.08
Calibration error (ECE)
Raw ADMET-AI → calibrated. A stated “0.80” now means roughly a real 0.80.
0.47–0.54
CYP AUROC on novel scaffolds
Independent ChEMBL de-leak (n=701 / 237) — near chance, so ToxScreen abstains rather than guess.
4 / 4
Endpoints de-leak-tested & published
We publish the failing and inconclusive numbers, not only the flattering ones.

Calibration — published in full, including where it fails

hERG (7CN1)
0.69 AUROC
FAIL (random split)
~0.84 calibrated (0.71 baseline) on novel chemistry
CYP3A4 (6MA7)
0.95 AUROC
PASS
in-dist. only — novel-chem AUROC 0.47 (n=701), ~chance
CYP2D6 (4WNT)
0.94 AUROC
PASS
in-dist. only — novel-chem test inconclusive (99% single-class)
CYP2C9 (1OG5)
0.94 AUROC
PASS
in-dist. only — novel-chem AUROC 0.54 (n=237), ~chance
It tells you when it doesn't know. CYP inhibition is AUROC 0.94–0.95 in-distribution (random-split calibration holdout) — but on an independent cross-dataset test (ChEMBL, InChIKey-filtered against ADMET-AI's training data), CYP3A4 and CYP2C9 AUROC drops to 0.47–0.54, statistically indistinguishable from chance; treat the headline CYP number as unvalidated for novel chemistry. hERG is the one target with an honest novel-chemistry number: 0.69 on a random split, and the calibrated ToxScreen pipeline (ChemBERTa applicability domain + isotonic re-weighting) reaches ~0.84 AUROC on de-leaked novel chemistry (ADMET-AI alone: 0.71). We calibrate conservatively and abstain when a compound falls outside the model's applicability domain instead of guessing. We publish the failing/unvalidated numbers, not just the flattering ones — see the Methodology page for the full de-leak writeup.
In-distribution vs. novel chemistry — every endpoint, side by side

The headline AUROCs (blue) are a random-split holdout of the same dataset the model trained on. The honest test is independent novel chemistry (ChEMBL, InChIKey-de-leaked). Where the two dots sit far apart, the in-distribution number does not transfer.

hERG blockade 7CN1 novel-validated
0.4.5.81.0 0.69 0.67

Random split 0.69; independent novel chemistry 0.67 (n=8,886). Stable, not inflated — the one endpoint with a real novel-chemistry number.

CYP3A4 inhibition 6MA7 in-dist only
0.4.5.81.0 0.95 0.47

In-distribution 0.95 collapses to 0.47 on novel chemistry (n=701) — a coin flip. Unvalidated for new scaffolds.

CYP2D6 inhibition 4WNT inconclusive OOD
0.4.5.81.0 0.94 novel: inconclusive

In-distribution 0.94. The novel-chemistry holdout was 99% single-class, so no honest AUROC can be reported.

CYP2C9 inhibition 1OG5 in-dist only
0.4.5.81.0 0.94 0.54

In-distribution 0.940.54 on novel chemistry (n=237) — near chance.

In-distribution — random-split calibration holdout Independent novel chemistry — ChEMBL, InChIKey-de-leaked chance (0.5) · screening bar (0.8)
Three of four CYP endpoints look excellent in-distribution (AUROC 0.94–0.95) but two of them fall to chance on independent novel chemistry, and the third can’t be tested honestly. We publish this gap rather than hide it — and the product abstains on out-of-domain compounds instead of reporting a number it can’t stand behind.
What calibration buys you — hERG on novel chemistry
0.5 0.7 0.8 bar 0.9 0.71 0.84 +0.13 AUROC ADMET-AI ToxScreen

On de-leaked novel chemistry, the calibrated ToxScreen pipeline (ChemBERTa applicability-domain re-weighting + isotonic calibration) lifts hERG discrimination from the raw ADMET-AI baseline 0.71 to 0.84 AUROC — and, just as important, fixes the model’s confidence:

0.32 → 0.08
Expected calibration error
Raw ADMET-AI → calibrated. Lower is better — a stated 80% is closer to a real 80%.
0.844 ±0.02
Novel-chem AUROC
3-seed mean ± SD, Karim cross-dataset with InChIKey de-leaking.
Calibration is the product. Raw model scores over-state their own confidence (ECE 0.32); after calibration a “0.80” means roughly a real 0.80 (ECE 0.08), and out-of-domain compounds are flagged for abstention rather than guessed.

Random-split benchmark, 3 seeds, n≈1,800 per target (ADMET-AI on ChEMBL-derived actives/inactives). See the Methodology page for full calibration status and known limitations.

Workflow

How it works

1

Submit a SMILES

Paste your compound's SMILES string. We validate with RDKit and canonicalize automatically — no account setup friction.

2

Calibrated ADMET scoring

ADMET-AI (a chemprop graph neural network) scores hERG, CYP3A4, CYP2D6 and CYP2C9, with isotonic-calibrated probabilities and Tanimoto applicability-domain abstention when a compound is outside the model's domain. Deterministic CPU inference, ~1–7 s per compound.

3

Report ready

Download a print-ready HTML, PDF, Excel or JSON report with traffic-light risk classification, the full ADMET profile, and the methodology behind every number.

Capabilities

Exactly what ToxScreen does

No mystery box. Here is the full surface area — every target, endpoint, format and integration — and, just as plainly, what it is not for.

4
CTI safety targets
hERG + CYP3A4 / 2D6 / 2C9, combined into one weighted Composite Tox Index.
15+
ADMET endpoints / compound
Absorption, distribution, metabolism, clearance and safety flags in every report.
1–7 s
Per-compound, on CPU
Deterministic — the same SMILES always returns the same result. No GPU, no queue.
5
Export formats
HTML, PDF, Excel, CSV, JSON — plus REST API, Python SDK and CLI.
CapabilityWhat it doesAvailable in
Screening engine
4-target CTI safety panel hERG blockade + CYP3A4 / 2D6 / 2C9 inhibition, weighted into a Composite Tox Index (0–1) across five risk bands. All plans
Extended ADMET panel 15+ supplementary endpoints — Caco-2, P-gp, BBB, PPB, Vd, clearance, half-life, Ames, DILI, carcinogenicity, LD50 and more. All plans
Applicability-domain abstention A Tanimoto domain check flags out-of-domain chemistry and abstains rather than reporting a number it can’t stand behind. All plans
Calibrated probabilities Isotonic + conformal calibration with intervals — a “0.8” is close to a real 0.8, not a raw model score. All plans
RDKit pre-flight Structure validation, canonicalization and PAINS / physicochemical sanity checks before any compound is scored. All plans
Reports & export
Multi-format reports Print-ready HTML, PDF, Excel, CSV and JSON — traffic-light verdict, full ADMET profile, and the methodology behind every number. All plans
Sample report gallery Real pipeline output for reference compounds, so you can inspect a full report before signing up. Public
Integration & workflow
REST API, Python SDK & CLI Documented endpoints (OpenAPI), a typed Python client, and a command-line tool for scripting screens into your pipeline. Starter +
Batch CSV upload Score up to 100 compounds per job from a single CSV, with per-row status and a combined report. Pro +
Signed webhooks HMAC-SHA256-signed completion callbacks so your systems react the moment a screen finishes. Pro +
Projects, CRO worklist & SAR tracking Group compounds into projects, export a CRO assay worklist, and track structure–activity-relationship trends over time. Pro +
Science & integrity
Published calibration — incl. failures Full per-endpoint status, the novel-chemistry de-leak test, and every known limitation — the flattering and the unflattering. Public
Zero mock data Every score traces to a real computation or a measured value. No placeholders, ever. Always

What ToxScreen is for

  • Early triage — flag hERG and CYP liabilities before you commit to synthesis or a wet-lab assay.
  • Prioritising a list — rank a set of candidates by calibrated computational risk.
  • Catching over-reach — know when a compound is too novel for the model to score, so you don’t trust a bad number.
  • A reproducible first pass — a cheap, deterministic filter that feeds a shortlist into the assays that matter.
  • An auditable rationale — a documented, calibrated risk story per compound you can hand to a colleague.

What ToxScreen is not

  • Not a lab replacement — it does not substitute for in vitro or in vivo toxicology.
  • Not a regulatory tool — not GLP, not IND-enabling, not an FDA / EMA / PMDA submission.
  • Not medical advice — no diagnosis, treatment, or clinical guidance; “low risk” is not “safe”.
  • Not a potency predictor — it estimates liability risk, not on-target activity or efficacy.
  • Not validated on novel CYP chemistry — where it can’t stand behind a number, it abstains instead of guessing.

Where we're headed

The same honesty-first engine, pointed at longevity.

ToxScreen catches your liabilities. The engine behind it now screens natural-product space for compounds that bind validated longevity targets — under the same rules that govern the tox panel: validated targets only, publish where it fails, abstain when the model doesn't know.

The validation scoreboard — every target, every gate

Each target must clear an adversarial scorecard before it can emit a single lead. We publish the whole board, passes and failures alike. Of seven candidates, one clears every gate.

Target Receptor Discrimination Neg-control Blinded holdout Verdict
PARP1 7AAD Green · emit leads
CD38 8D0M Blocked
AMPK 4CFE Blocked
SIRT1 4I5I Blocked
KEAP1 4L7B Blocked
BCL-XL 2YXJ Blocked
mTOR 4JSV Blocked
  gate passed   gate failed   not established (insufficient data)
The authoritative target-card panel, generated 2026-07-09. 1 of 7 targets is GREEN — PARP1, the only one to clear receptor fit, binder-vs-decoy discrimination, a negative-control false-positive gate, and a 3-of-3 blinded holdout. Every other candidate fails at least one gate and is held back. We would rather ship one honest target than seven hopeful ones.
Why discrimination alone isn’t enough
−0.5 0.0 0.5 1.0 0.80 screening bar PARP1 1.00 / 0.33 ✓ validated AMPK 0.99 / 0.34 ✗ neg-control BCL-XL 0.94 / 0.66 ✗ unvalidated SIRT1 0.82 / 0.48 ✗ neg-control KEAP1 0.66 / −0.39 ✗ discrimination
Discrimination — retrospective ROC-AUC (binders vs decoys) Potency ranking — Spearman ρ (vs measured affinity)
The same targets, on raw retrospective signal. Four of five separate binders from decoys respectably (AUC 0.82–0.99) — yet on the scoreboard above only PARP1 survives. High discrimination is necessary but not sufficient: AMPK and SIRT1 also light up against inert negative-control metabolites (false positives), BCL-XL can’t be validated on the few measured actives available, and KEAP1 fails discrimination outright. Ranking potency (ρ) is harder still and remains the open frontier. Boltz-2 retrospective benchmark vs measured ChEMBL bioactivity, n = 17–42 per target. CD38, previously charted here, was withdrawn after its reference set was traced to the wrong protein; it is Blocked on the scoreboard above.
How a natural product becomes a lead
1

Validate the target

Before a target can emit a single lead it must clear an adversarial scorecard — discrimination, negative-control false-positive rate, and a blinded holdout. Most candidate targets fail. We publish which, and why.

2

Screen natural-product space

Structure-based co-folding scores each compound against the validated pocket. Novel scaffolds are welcome — a physics-informed model generalises across chemotypes, so unprecedented natural products are candidates, not noise.

3

Kill the artifacts

Each hit is re-scored against a panel of unrelated proteins. Bind the target but not the decoys → a real, selective hit. Bind everything → a frequent-hitter artifact, discarded. PAINS and aggregation filters run alongside.

4

Rank, and caveat honestly

What survives is a ranked list of target-selective binder hypotheses — with an explicit confidence flag and the plain statement that these are computational leads for follow-up, not potency claims.

PARP1 — the one target that has cleared every gate
PARP1 catalytic domain (PDB 7AAD) with olaparib bound in the pocket
The NAD⁺-consuming enzyme PARP1 (catalytic domain, PDB 7AAD) with the inhibitor olaparib bound in the pocket (green sticks). It is the only target in our panel that passes every gate — discrimination, negative-control, and a 3-of-3 blinded holdout. Explore it in 3D on RCSB →
The aspiration: turn natural-product space into an auditable pipeline of ranked, target-selective longevity hit hypotheses — validated against real bioactivity, honest about every number, no over-claiming.

Computational hit hypotheses for research — not validated therapeutics. Experimental confirmation required.

Live sample

See a real report

Every report below is generated offline by the real pipeline — pick a compound.

Generating report…

Pricing

Simple, transparent pricing

Start free — no credit card. Upgrade when the screenings pay for themselves.

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  • 4-target CTI safety panel
  • Extended ADMET panel (15+ endpoints)
  • HTML + PDF + Excel + JSON reports
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$49/mo
10 screenings / month
  • 4-target CTI safety panel
  • Extended ADMET panel (15+ endpoints)
  • HTML + PDF + Excel + JSON reports
  • API key access
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Enterprise
$999/mo
Unlimited screenings
  • Everything in Pro
  • Unlimited screenings
  • API key + webhooks
  • CRO worklist export
  • Dedicated support
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