A clinical terminology platform that takes care of the heavy lifting.
The heavy lifting: loading every code system and keeping it up to date, managing the licences, mapping between systems and telling you how much to trust each map, and more. Codon does it so your team don't have to — hosted in Europe, or on your own servers.
Official content, unchanged · every mapping rated · licences tracked · hosted in Europe or on your own servers.
Try it yourself, right here.
Demo queries are throttled to 5 per 30 seconds by a browser-side courtesy limit.
For developers
Every request above is a standard FHIR R4 API call. Copy the curl command, or explore the full API in our interactive documentation.
Every mapping tells you how much you can trust it.
A mapping from one code system to another can be exact, or only approximate. Codon rates each one and shows that rating wherever the mapping is used — together with how the rating was determined.
Strong, Review-recommended, or Manual — specific to the two systems being mapped, and shown wherever the mapping appears.
Each rating is measured against a public benchmark, carries a version, and is updated with every release. No rating is ever shown without the method behind it.
The ratings are tested, not just claimed.
Every pair is rated separately
Some mappings are close to exact, like LOINC to NPU. Others lose detail no matter how carefully they are made, like SNOMED CT to ICD-10. A single accuracy figure would hide that difference, so Codon rates each pair on its own.
Nothing taken on trust
Every rating is measured against a public benchmark you can look up yourself — not a number you have to take on our word.
A document, not an adjective
For each mapping set, the rating comes as a report you can download and attach straight to a submission.
What Codon does.
Terminology operations
Look up, validate, translate and expand clinical codes — across SNOMED CT and every other code system you load, through one standards-based FHIR R4 API.
Cross-system translation
Translate a code from one loaded system to another through their concept maps. Where there is no direct map, Codon chains existing maps through intermediate systems — every hop is a real crossmap, never an inferred one. And if no chain exists either, you get an honest no-match, not an invented answer.
Mapping suggestions a person signs off
Optional suggestions that speed up mapping work. A person approves, rejects or edits each one — nothing is accepted automatically, and you can turn suggestions off and map by hand.
De-identification
Find and pseudonymise patient identifiers in clinical free text before the text goes anywhere else. Processing stays in-region, inside the platform.
Encounter validation
Check encounters against registry rules and extract the codes before you submit — so problems are caught before they ever reach the registry.
Versioning & audit
Versioned releases, full change history, and a tamper-evident audit trail — so every change to clinical meaning is accountable.
What people use it for.
Some of the jobs Codon is used for:
Terminology as an API
A product team calls one standards-based API to look up, validate, translate, and expand codes — instead of building and running terminology infrastructure in-house.
validation · translationEmbed the terminology layer
A platform vendor puts code search, text-to-code suggestions, and cross-system translation inside their own interface, with the terminology layer running behind it.
extraction · translationValidate before submission
A data team checks encounters against national registry rules and resolves the flagged issues before submitting.
validationRemove patient identifiers from clinical text
A team replaces patient identifiers in clinical notes for a data-reuse workflow, with the text never leaving their own environment.
de-identificationCode free-text notes
Coders get diagnosis and procedure suggestions drawn from clinical notes — each one a draft a person confirms, with negation and timing flagged.
extractionAuthor & release official content
An authority maintains its own classification in a private workspace, cuts a versioned release, and publishes it with append-only history and a tamper-evident trail.
authoringTrack licensed-vocabulary entitlements
A safety and standards team tracks entitlements, usage, and audit across its own licensed clinical vocabularies — in one place.
licence managementSee what a version change breaks
A team compares two releases of a vocabulary concept by concept and identifies what changes in its data before the upgrade lands.
mappingTranslate decades of registry data
Researchers translate historical registry data from legacy ICD revisions through ICD-10 and ICD-11 to SNOMED CT, using published intermediary maps, and export the harmonised set.
translation · mappingMap to a common data model
An evidence team maps internal source codes to the OMOP common data model, with suggestions a person reviews and a record of every decision.
mappingModernise legacy messages
An integration project converts legacy clinical messages into profile-conformant FHIR, with terminology validated in flight rather than after the fact.
validation · translationA terminology backend
A third-party platform calls Codon in production to validate and translate codes behind its own product.
validation · translationThis is a sample, not the full list. Tell us the job you have in mind.
Optional, marked, and never left to decide on its own.
Codon can run with no AI at all. When it is used, these rules apply:
- ✓You can turn it off. Every terminology and mapping operation works with the AI switched off entirely.
- ✓It's marked. Anything the AI produced is labelled as such in the data and carried into the exports, following the EU AI Act Article 50 format.
- ✓Nothing is accepted on its own. A person signs off on every suggestion.
- ✓It can say no. When it isn't sure enough, it declines to suggest instead of guessing.
- ✓Every change is recorded. A tamper-evident log records who changed which mapping, and when.
You decide where your data lives.
By default, Codon runs as a hosted service in Europe — EU-owned and in-region, outside US jurisdiction. You can run it in another region, or entirely on your own servers, instead.
Official content, plus your own. The built-in catalogue holds authority-published terminology and mappings only — nothing made up or derived is passed off as official. Alongside it you can keep your own content — custom code systems, value sets, and maps — private to you and kept separate from the official catalogue.
Global standards, with strong Nordic coverage.
These figures count the official, authority-published catalogue only — from SNOMED International, NLM, WHO, Regenstrief, and national authorities. Your own content is extra and not counted here. Shown live from the catalogue, with no padding.
Pricing
Start with the free tier. Upgrade when you need more.
Foundation
Try the API and build a prototype
- Look up and check codes through the FHIR API (read-only)
- Read access to the code systems your licence permits
- 1,000 API calls a month
- No credit card required
Insight
For teams using the API in production
- Everything in Foundation
- Translate codes, including multi-step, and run advanced concept queries (ECL)
- Build and manage your own value sets and mappings
- AI query assist: plain language to concept queries, with explanations
- Single sign-on (SSO)
- 1 million API calls a month; CSV and HL7v2 export
Clinical
For clinical coding, hospital IT, and research teams
- Everything in Insight
- All AI mapping methods, with a human review queue
- AI text coding that understands negation and time
- Author codes, set up workflows, manage releases
- 10 million API calls a month, all 9 export formats
Enterprise
For EHR vendors, regions, and national agencies
- Everything in Clinical
- Your own dedicated environment
- Run it on your own servers if you prefer
- Custom SLA and call volume
- Patient-data processing included
Compare plans
| Foundation | Insight | Clinical | Enterprise | |
|---|---|---|---|---|
| Price | €0 | €299/mo | €1,499/mo | Custom |
| Monthly ops budget | 1K | 1M | 10M | Custom |
| Rate limit (sustained) | 10 req/s | 50 req/s | 200 req/s | 500 req/s |
| FHIR R4 read ($lookup, $validate-code, $autocomplete) | ✓ | ✓ | ✓ | ✓ |
| $expand, $closure, $batch, $subsumes | — | ✓ | ✓ | ✓ |
| $translate + multi-hop translate | — | ✓ | ✓ | ✓ |
| ECL queries | — | ✓ | ✓ | ✓ |
| ValueSet authoring + mapping workspace | Read-only | ✓ | ✓ | ✓ |
| FHIR resource suite (forms, knowledge artifacts, profiles, care pathways) | — | — | ✓ | ✓ |
| Clinical text coding | — | — | ✓ | ✓ |
| AI mapping (suggest, infer, cross-lingual, analogical) | — | — | ✓ | ✓ |
| AI query assist (NL→ECL, explain) | — | ✓ | ✓ | ✓ |
| AI editorial assist (release notes, scope notes, retirement impact) | — | — | ✓ | ✓ |
| Code set management (authoring, workflows, releases) | — | — | ✓ | ✓ |
| Terminology insight & analytics | — | — | ✓ | ✓ |
| Terminology sharespace (share value sets, mappings, supplements) | — | — | ✓ | ✓ |
| Export formats | — | CSV + HL7v2 | All 9 | All 9 |
| Format conversion (HL7v2, CDA, IPS) | — | — | ✓ | ✓ |
| Bulk data export | — | — | ✓ | ✓ |
| FHIR Subscriptions | — | — | ✓ | ✓ |
| SSO / OIDC sign-in | — | ✓ | ✓ | ✓ |
| PHI processing (LPR validate, extract-codes, de-identify) | — | Add-on | Add-on | Included |
| On-premise deployment | — | — | — | Optional |
| Custom code systems | — | — | ✓ | ✓ |
| Soft-cap overage | — | — | — | ✓ |
| Custom SLA & uptime | — | — | — | ✓ |
| Dedicated onboarding & support | — | — | — | ✓ |
PHI processing is a contracted add-on enabled with a signed DPA, and is included with Enterprise. On-premise deployment is available on Enterprise.
Paid plans include a 14-day trial. PHI processing is available as an add-on with a signed DPA.
Contact
Have questions or need help choosing the right tier? Send us a message. We respond within one business day.
Codon is in a controlled evaluation phase. Request access
See how good your mappings are.
Tell us the code systems and mappings you work with. We'll show you the ratings, the AI controls, and a sample report to take away.
In English, Danish, and Norwegian, with more languages to come.