Document and Entity Information	3 Months Ended
Mar. 31, 2018
Document And Entity Information
Entity Registrant Name	SIGMA LABS, INC.
Entity Central Index Key	0000788611
Document Type	S-1/A
Document Period End Date	Mar. 31, 2018
Amendment Flag	true
Amendment Description	Amendment No. 2
Entity Filer Category	Smaller Reporting Company
Trading Symbol	SGLB

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Description of changes contained within amended document.

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If the value is true, then the document is an amendment to previously-filed/accepted document.

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The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD.

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The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word "Other".

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- Definition

A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation 12B
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Indicate whether the registrant is one of the following: (1) Large Accelerated Filer, (2) Accelerated Filer, (3) Non-accelerated Filer, (4) Smaller Reporting Company (Non-accelerated) or (5) Smaller Reporting Accelerated Filer. Definitions of these categories are stated in Rule 12b-2 of the Exchange Act. This information should be based on the registrant's current or most recent filing containing the related disclosure.

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The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Trading symbol of an instrument as listed on an exchange.

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