Technology Readiness Level (TRL)

Technology Readiness Level (TRL) is a standardized 1–9 scale that describes how mature a specific technology is, from basic scientific principles first observed (TRL 1) to an actual system proven through successful operations in its real deployment environment (TRL 9). It was originally developed at NASA in the 1970s and formalized as a nine-level scale in the early 1990s. The terms “technology readiness level” and “technical readiness level” are used interchangeably in practice — both refer to the same scale (TRL is the standard abbreviation either way).

TRL rates the technology itself, independent of funding source, market opportunity, or how promising a result looks in a journal article. A technology’s TRL answers one question: has it actually been built and tested, and if so, under what conditions — a bench-top simulation, a controlled lab environment, or its real operational setting? Two technologies can be equally patentable, equally well-funded, and equally exciting scientifically while sitting at very different TRLs, because TRL only tracks demonstrated physical/functional maturity.

The nine TRL levels

The definitions below are NASA’s original nine-level scale, which the U.S. Department of Defense, the Department of Energy, and most other adopters use with only minor wording variations (see “Who else uses TRL” below for where the wording genuinely diverges).

TRL	Definition
1	Basic principles observed and reported
2	Technology concept and/or application formulated
3	Analytical and experimental critical function and/or characteristic proof-of-concept
4	Component and/or breadboard validation in laboratory environment
5	Component and/or breadboard validation in relevant environment
6	System/subsystem model or prototype demonstration in a relevant environment
7	System prototype demonstration in an operational environment
8	Actual system completed and qualified through test and demonstration
9	Actual system proven through successful operations

Read as three bands rather than nine isolated steps, the scale is easier to apply in practice:

• TRL 1–3 — basic research. The work is still happening on paper, in simulation, or on the lab bench in isolated form: a principle is observed, an application is proposed, and a proof-of-concept experiment or analysis confirms the critical function could work. Most sponsored academic research, and most invention disclosures a technology transfer office (TTO) first receives, sit in this band.
• TRL 4–6 — development and validation. Individual components are integrated and tested first in a controlled lab setting (TRL 4), then in an environment that increasingly resembles real operating conditions (TRL 5), culminating in a working prototype or system-level model demonstrated in a relevant environment (TRL 6). This band is where most pilot programs, translational grants, and early-stage licensing conversations happen.
• TRL 7–9 — deployment. A prototype, then a qualified system, then a fully proven system operate in the actual conditions the technology is meant for. By TRL 9 the technology is no longer a research output at all — it is a deployed, operating product or system.

Who else uses TRL, and where the wording diverges

TRL did not stay a NASA-only tool. It is now the common vocabulary for technology maturity assessment across several major funders and standards bodies a TTO regularly deals with:

• U.S. Department of Defense (DoD) adopted TRL for acquisition program reviews in the early 2000s; DoD’s wording for the upper levels refers to an operational environment rather than NASA’s original space-mission-specific phrasing (NASA’s own levels 7 and 9, written for spaceflight hardware, historically referred to a “space environment” and being “flight proven”).
• U.S. Department of Energy (DOE) uses a tailored version of the NASA/DoD model in its Technology Readiness Assessment (TRA) process for capital-asset projects under DOE Order 413.3B, applying the same nine levels to energy technologies rather than spaceflight hardware.
• The European Commission defines TRL 1–9 in the General Annexes of its Horizon Europe (and previously Horizon 2020) work programme, using it to set eligibility and expected maturity bands for different funding instruments — a proposal pitched at TRL 2 is not competitive for a call designed for TRL 6–8 technologies, and vice versa.
• ISO 16290:2013 standardizes TRL definitions specifically for space systems, formalizing NASA’s original scale as an international standard.
• University TTOs use TRL, often informally, as shorthand in invention disclosures, licensing memos, and internal portfolio reviews — not because a university is contractually required to assign a TRL, but because it is the shared vocabulary every federal funder, corporate licensing partner, and venture investor a TTO deals with already understands.

Why a technology transfer office cares about TRL

TRL is not primarily a research-management curiosity for a TTO — it does two concrete jobs in the commercialization workflow:

• Commercialization-readiness triage. When an invention disclosure arrives, its approximate TRL is one of the fastest signals a TTO has for what happens next. A TRL 2–3 disclosure (an early proof-of-concept) usually needs further institutional or grant-funded development, and possibly a provisional patent application filed early to preserve rights while that development continues, before it is licensable to an established company. A TRL 6–7 disclosure (a demonstrated prototype in a relevant environment) is often ready to shop directly to industry, since most companies want to acquire technology past the point where they would have to fund the earliest, highest-risk development themselves. See CASRAI’s guide on patent licensing for how licensing terms typically shift with a technology’s maturity.
• Funding-stage matching. Federal and philanthropic translational-research programs are frequently scoped to a specific TRL band, and matching a technology to the right instrument at the right stage is a core TTO function. For example, NSF’s Regional Innovation Engines program explicitly frames its initial R&D as spanning TRL 1–5, with the expectation that an Engines award itself advances a technology further along that scale. SBIR/STTR awards similarly track a technology’s progression — a Phase I feasibility award and a Phase II development award are pitched at meaningfully different maturity levels for the same underlying technology. A TTO that can accurately place a technology on the TRL scale can point faculty toward the funding mechanism that actually fits where the work currently is, rather than one scoped for a later (or earlier) stage.

TRL also gives a TTO a maturity-independent way to talk to non-technical stakeholders — a licensing committee, a university leadership team, or an industry partner — about how much development risk remains, without needing every listener to understand the underlying science in detail.

What TRL is not

TRL measures technical/functional maturity only. It does not, by itself, measure market size, competitive positioning, regulatory pathway complexity, manufacturing scalability, or how much funding has been raised — a technology can sit at a high TRL and still fail commercially for reasons entirely outside the scale, and a low-TRL technology can already have a large addressable market and strong investor interest well before it is technically deployable. Some agencies and programs pair TRL with a separate commercial- or market-readiness assessment specifically because TRL was never designed to capture that dimension on its own.

TRL is also distinct from, though sometimes confused with, patentability and Bayh-Dole timing. A technology can be patentable at TRL 2–3 (an analytical or experimental proof-of-concept is often enough to support a patent claim) long before it is deployable at TRL 8–9 — which is exactly why TTOs frequently file an early provisional patent application to preserve priority while the underlying technology continues to mature through the TRL scale over the following months or years.

Related CASRAI resources

• Technology Transfer & Innovation — cluster overview
• Translational research
• SBIR (Small Business Innovation Research)
• Patent Licensing: Exclusive Terms, Royalties, and Startup vs. Established Deals
• Industry-University Research Partnerships: Agreement Structures and IP Terms
• Provisional Patent Applications: USPTO Requirements, Cost, and the 12-Month Deadline