Validate your LAMP primer set before ordering. Nearest-neighbour Tm, GC content, length constraints, 3′-end stability, and pair Tm differences — all checked against Notomi guidelines in one click.
Try it out
Load example LAMP primer Tm checker data to see the full workflow
Enter your LAMP primer sequences (5\u2032 \u2192 3\u2032). F3, B3, FIP, and BIP are required. LF and LB (loop primers) are optional.
When to use
Do not use for
The Tm shown for FIP and BIP is the full-length nearest-neighbour Tm of the entire composite sequence (F1c+F2 or B1c+B2). In practice, each half anneals independently. Consider this when comparing Tms across primer types.
LF and LB are optional but typically reduce time-to-positive by 50%. If your assay runs long without them, add loop primers and validate here.
LAMP buffers vary by vendor. Default is 50 mM Na⁺. If using a different buffer, adjust the [Na⁺] field. A 2-fold change in salt can shift Tm by 3–5 °C.
Unlike PCR where only two primers need to match, LAMP has 4–6 primers that must all work at the same temperature. Tm differences > 5 °C between pairs reduce amplification efficiency.
If time-to-positive is unexpectedly long, check 3′-end ΔG. Primers with weak 3′ ends (ΔG > −8 kcal/mol) may need redesign with GC-rich 3′ tails.
Tm = SantaLucia (1998) nearest-neighbour with salt correction (ΔS + 0.368(N−1)ln[Na⁺]). 3′-end ΔG = nearest-neighbour ΔG of last 5 bases at 37 °C. Length, GC, and Tm validated per Notomi et al. (2000) guidelines. Pair Tm differences checked against 5 °C maximum.
Last validated 2026-04-07. Calculations are designed for planning and documentation support; verify procurement decisions against manufacturer specifications or institutional SOPs.
ConductScience LAMP Primer Tm + GC Checker (v1.17.0). ConductScience, Inc. 2026. Available at: https://conductscience.com/tools/lamp-primer-tm-checker
Notomi T et al. Loop-mediated isothermal amplification of DNA. Nucleic Acids Res. 2000;28(12):e63. doi:10.1093/nar/28.12.e63
SantaLucia J Jr. A unified view of polymer, dumbbell, and oligonucleotide DNA nearest-neighbor thermodynamics. PNAS. 1998;95:1460–1465. doi:10.1073/pnas.95.4.1460
LAMP (Loop-mediated isothermal AMPlification) uses a strand-displacing DNA polymerase (typically Bst) and 4–6 primers to amplify DNA at a constant temperature of 60–65 °C. Unlike PCR, LAMP does not require thermal cycling.
The reaction proceeds through a series of self-priming steps: 1. F3/B3 (outer primers) initiate strand displacement 2. FIP/BIP (inner primers) create dumbbell-shaped intermediates 3. LF/LB (loop primers) accelerate amplification by priming within loops
The result is a concatemer of alternating inverted repeats, producing 10⁹–10¹⁰ copies in 30–60 minutes.
LAMP primers must satisfy several constraints for reliable amplification:
These guidelines are from Notomi et al. (2000) and NEB LAMP technical resources.
This tool uses the SantaLucia (1998) unified nearest-neighbour model:
Where ΔH and ΔS are summed from all dinucleotide steps plus initiation parameters. Salt correction adjusts ΔS:
Default conditions: [Na⁺] = 50 mM, [oligo] = 0.25 µM, matching typical LAMP buffer conditions.
