Primer3Plus
pick primers from a DNA sequence
Primer3Manager
Help
About
Source Code
Please select the Task here:
Detection
Cloning
Sequencing
Primer_List
Primer_Check
Go to Javascript version
Detection:
Pick primers anywhere in the Sequence using targets and regions.
Cloning:
Pick primers exactly at the border of included region.
Sequencing:
Pick primers for sequencing along the sequence using targets and regions
Primer List:
Pick a list of primers along the sequence using targets and regions
Primer Check:
Check a primer provided in left primer input
Sequence Id:
Mispriming/Repeat Library:
NONE
HUMAN
RODENT_AND_SIMPLE
RODENT
DROSOPHILA
A name to identify your output.
Or N-out undesirable sequence (vector, ALUs, LINEs...)
To upload or save any sequence from your local computer, choose here:
Paste source sequence below:
5'->3', as ACGTNacgtn -- other letters treated as N -- numbers and blanks ignored FASTA format ok.
Pick left primer
or use left primer below.
Pick hybridization probe
(internal oligo) or use oligo below.
Pick right primer or use right primer
below (5'->3' on opposite strand).
Excluded Regions:
<
>
E.g. 401,7 68,3 forbids selection of primers in the 7 bases starting at 401 and the 3 bases at 68. Or mark the source sequence with < and >: e.g. ...ATCT<CCCC>TCAT.. forbids primers in the central CCCC.
Targets:
[
]
E.g. 50,2 requires primers to surround the 2 bases at positions 50 and 51. Or mark the source sequence with
[ and ]: e.g. ...ATCT[CCCC]TCAT.. means that primers must flank the central CCCC.
Included Region:
{
}
E.g. 20,400: only pick primers in the 400 base region starting at position 20. Or use { and } in the
source sequence to mark the beginning and end of the included region:
e.g. in ATC{TTC...TCT}AT the included region is TTC...TCT.
Please select special settings here:
Default
qPCR
Probe
Use_Product_Size
To upload or save a settings file from your local computer, choose here:
Product Size Ranges
Primer Size
Min:
Opt:
Max:
Primer Tm
Min:
Opt:
Max:
Max Tm Difference:
Primer GC%
Min:
Opt:
Max:
Salt Concentration:
Fix the
prime end of the primer
Annealing Oligo Concentration:
Select which end of the primer is fixed and which end can be extended or shortened by Primer3Plus fo find optimal primers.
(Not the concentration of oligos in the reaction mix
but of those annealing to template.)
General Sequencing Conditions
Lead
Bp:
Space between primer binding site and the start of readable sequencing
Spacing
Bp:
Space between the primers on one DNA strand
Accuracy
Bp:
Space in which Primer3Plus picks the optimal primer
Pick Reverse Primers
Pick also primers on the reverse DNA strand
Interval
Bp:
Space between primers on the forward and the reverse strand
Max #N's:
Max Poly-X:
Number To Return:
CG Clamp:
Max Self Complementarity:
Max 3' Self Complementarity:
Max 3' Stability:
Max Mispriming:
Pair Max Mispriming:
Left Primer Acronym:
Internal Oligo Acronym:
Right Primer Acronym:
Primer Name Spacer:
Product Tm
Min:
Opt:
Max:
Use Product Size Input and ignore Product Size Range
Warning: slow and expensive!
Select box to specify the min, opt, and max product sizes only if you absolutely must!
Using them is too slow (and too computationally intensive for our server).
Product Size
Min:
Opt:
Max:
Liberal Base
Show Debuging Info
Do not treat ambiguity codes in libraries as consensus
Hyb Oligo Size:
Min:
Opt:
Max:
Hyb Oligo Tm:
Min:
Opt:
Max:
Hyb Oligo GC%
Min:
Opt:
Max:
Hyb Oligo Salt Concentration:
Hyb Oligo DNA Concentration:
Max #Ns:
Hyb Oligo Max Poly-X:
Hyb Oligo Self Complementarity:
Hyb Oligo Max 3' Self Complementarity:
Hyb Oligo Max Mishyb:
Hyb Oligo Min Sequence Quality:
Hyb Oligo Mishyb Library:
NONE
HUMAN
RODENT_AND_SIMPLE
RODENT
DROSOPHILA
Hyb Oligo (Internal Oligo) Per-Sequence Inputs
Hyb Oligo Excluded Region:
Other Per-Sequence Inputs
First Base Index:
Sequence Quality:
Start Codon Position:
Min Sequence Quality:
Min End Sequence Quality:
Sequence Quality Range Min:
Sequence Quality Range Max:
For Primers
For Primer Pairs
For Hyb Oligos
Tm
Lt:
Gt:
Product Tm
Lt:
Gt:
Tm
Lt:
Gt:
Size
Lt:
Gt:
Product Size
Lt:
Gt:
Size
Lt:
Gt:
GC%
Lt:
Gt:
GC%
Lt:
Gt:
Mispriming
Pair Mispriming
Hyb Oligo Mishybing
Self Complementarity
Self Complementarity
Self Complementarity
3' Complementarity
3' Complementarity
#N's
Hyb Oligo #N's
Sequence Quality
Sequence Quality
End Sequence Quality
Position Penalty
Tm Difference
End Stability
Primer Penalty Weight
Inside Target Penalty:
Hyb Oligo Penalty Weight
Outside Target Penalty:
Set Inside Target Penalty to allow primers inside a target.