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Codon Valuation

ChatGPT plugin

409A and EMI value estimates

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Codon Valuation estimates the value of a private company's common stock (US) or ordinary shares (UK) before a formal valuation.

Give it the company's cap table and finances, such as share counts by class, the last priced round, revenue, cash and debt, and it returns an indicative low, mid and high value per share with the method and every assumption shown. The method follows what the company provides: an option pricing model calibrated to a recent priced round, a roll-forward of an older round blended with a revenue multiple, a sector revenue multiple, or an asset-based range for pre-revenue companies. Value is allocated across share classes with a Black-Scholes option pricing model, then a discount for lack of marketability is applied using the Finnerty and Chaffe models.

It also explains the documents and process for a formal IRC 409A valuation or an HMRC EMI valuation.

All tools are read-only. Nothing is stored, no account is needed, and the tools do not ask for names or other personal information. Results are indicative planning estimates: they are not a 409A valuation, do not provide safe harbor protection, and are not a valuation agreed with HMRC.

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Rank by placement

#8087of 11,36024places up24h1,039places up7d
#7,260#7,770#8,280#8,790Oct 6Oct 12Oct 18Oct 24Oct 30Nov 4

Rank in Finance

#685of 9351places up24h81places up7d
#623#662#701#740#779Oct 6Oct 12Oct 18Oct 24Oct 30Nov 4

In its category

How this plugin compares with others in the same category. Positions are counted within the category, not across the whole directory.

Finance685th of 935 by placement
#PluginPosition7d
683Zeno Bookkeeper#8067848places up
684Remitly#8085493places up
685Codon ValuationThis page#80871,039places up
686LuxAlgo#8099602places up
687MayRetire#8103422places up

All 935 Finance plugins

Also on other marketplaces

Example prompts

  • “We raised a $10M Series A at $2.00 a share four months ago, with 8M common and 5M preferred shares. Estimate our 409A value.”
  • “Our UK startup has 1M ordinary shares, £800k revenue and no priced round. Roughly what would our EMI exercise price be?”
  • “What documents do I need for a 409A and an EMI valuation?”

Skills

  • get-started

    How to estimate a private company's 409A or EMI share value with the Codon Valuation tools, which inputs to collect, and how to present the result.

Categories
Made by
Codon Valuation Advisors LLC · Website
Sign-in
On Install
Capabilities
Estimate a US 409A common stock value from cap table and financial inputs, Estimate a UK EMI ordinary share value, with AMV and UMV context, Show the valuation method, assumptions and share class allocation behind each estimate, Explain the documents and process for a formal 409A or EMI valuation
Availability
Available
Version
1.0.0
Keywords
409A, EMI, valuation, cap table, share options, startup
Created
October 18, 2026
More info
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