COMPRESS, PV Elite, and DesignCalcs are full [ELI-REVIEW: ASME] pressure vessel design packages built to produce stamped-calculation-ready reports for a final, code-compliant vessel design, and they are licensed and priced for that purpose. ColdCalcs is a free, browser-based set of preliminary sizing calculators: full results appear on screen with no account and no install, but every result is explicitly preliminary and is not a substitute for a full-code design package or for review by a qualified engineer. Which one you reach for depends on where you are in a project — early conceptual sizing, or a final calculation package.
What each category is for
Full-code packages model a vessel in detail against essentially the full scope of [ELI-REVIEW: ASME Section VIII] (and often other codes: piping, wind/seismic, nozzle reinforcement, and more), and are built for engineers who need a complete, auditable, stamp-ready calculation report as a project deliverable. ColdCalcs is built for a narrower, earlier job: getting a fast, free, preliminary size and thickness estimate in a browser, with no license and no install, to support conceptual-stage decisions before a full design package is engaged.
| Tool | Purpose | Output type | Code scope | Platform | Price class |
|---|---|---|---|---|---|
| COMPRESS | Full ASME vessel design and code-compliance calculation software [ELI-REVIEW: verify] | Stamped-calculation-ready reports [ELI-REVIEW: verify] | Broad ASME Section VIII (and related) code coverage [ELI-REVIEW: verify] | Desktop application [ELI-REVIEW: verify] | Commercial per-seat license [ELI-REVIEW: verify] |
| PV Elite | Full ASME vessel (and related piping) design and code-compliance software [ELI-REVIEW: verify] | Stamped-calculation-ready reports [ELI-REVIEW: verify] | Broad ASME Section VIII (and related) code coverage [ELI-REVIEW: verify] | Desktop application [ELI-REVIEW: verify] | Commercial per-seat license [ELI-REVIEW: verify] |
| DesignCalcs | Full ASME vessel design and code-compliance calculation software [ELI-REVIEW: verify] | Stamped-calculation-ready reports [ELI-REVIEW: verify] | ASME Section VIII code coverage [ELI-REVIEW: verify] | Desktop application [ELI-REVIEW: verify] | Commercial per-seat license [ELI-REVIEW: verify] |
| ColdCalcs | Free preliminary sizing for refrigeration pressure vessels and coils | On-screen results; not a stamped-calculation report | [ELI-REVIEW: ASME VIII-1 shell/head thickness sizing, plus IIAR-2-referenced checks] | Browser, no install, no account required for results | Free (paid tier adds PDF export and saved projects only) |
Why this comparison is framed this way
A full-code package and a free preliminary calculator are not competing for the same job. Using ColdCalcs in place of a full design package on a final, stamped deliverable would be a misuse of the tool; using a full-code package for a five-minute conceptual sizing check is often more tool than the moment needs. ColdCalcs does not claim to replace a full-code package, does not produce a stamped or certified output, and every page on this site says so — see the disclaimer at the bottom of this page.
Run it
See ColdCalcs' four free preliminary sizing calculators, with full results on screen and no account required.
Browse the ColdCalcs tools →FAQ
Can ColdCalcs replace COMPRESS, PV Elite, or DesignCalcs for a final design?
No. ColdCalcs produces preliminary, on-screen sizing results only. It does not produce a stamped-calculation-ready report and is not a substitute for a full-code design package on a final project deliverable.
Does ColdCalcs produce a stamped or certified calculation report?
No. ColdCalcs does not review, approve, seal, or certify any result, and does not produce a stamped calculation report. Every result must be independently verified by a qualified engineer before use.
Why is ColdCalcs free when the full-code packages are not?
ColdCalcs targets a narrower, earlier stage of the design process (fast preliminary sizing) than a full-code package, and is built to be useful with no account and no install. Full-code packages cover far more code scope and produce a different class of deliverable, which is reflected in how they're priced.
Should I use ColdCalcs for early conceptual sizing?
ColdCalcs is built for exactly that: a fast, free, preliminary estimate to support early decisions, before a full-code package and a qualified engineer's review take a design to a final, stamped deliverable.