Simple Interest Calculator

Q: Finding Principal in simple interest

P = SI / (1 + RT).P is Prinicipal, SI = Simple Interest Final Amount, R = Interest Rate, T = time in years .

Simple interest is calculated by multiplying the rate of interest by the principal and duration

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Interest Calculator

Principal Amount

Interest Rate

Duration

Duration Unit

Reverse Calculate

Interest Amount

Total Amount (incl. Interest)

Principal Amount: 5000

Interest Rate : 7%

Duration (Years): 1

Total Amount : 5350

Interest Amount : 350.00

Simple Interest Formula

Find Interest Amount with Principal, Interest Rate and Time

Interest = P x T x R / 100

P is Prinicipal

R= interest rate / annum

T = time in years

Final Amount using Principal, Interest Rate and Time

SI = P * ( 1 + RT)

P is Prinicipal

SI = Simple Interest Final Amount

R= interest rate / annum

T = time in years

Find Principal with Final Amount, Interest Rate and Time

P = SI / (1 + RT)

Find Interest Rate with Principal, Final Amount and Time

R = (1 / T) (A / P - 1)

Find Time / Duration given Principal , Final Amount and Rate

T = (1 / R) (A / P - 1)

Simple Interest Rate Calculator table

You can change the Principal and Interest Rates in the fields above and view the Interest and Final Amount automatically for different durations

Principal : 5000

Interest Rate : 7%

Duration	Interest	Final Amount
1 Month	29.17	5029.17
2 Months	58.33	5058.33
3 Months	87.50	5087.50
4 Months	116.67	5116.67
5 Months	145.83	5145.83
6 Months	175.00	5175.00
7 Months	204.17	5204.17
8 Months	233.33	5233.33
9 Months	262.50	5262.50
10 Months	291.67	5291.67
11 Months	320.83	5320.83
12 Months	350.00	5350.00
13 Months	379.17	5379.17
14 Months	408.33	5408.33
15 Months	437.50	5437.50
16 Months	466.67	5466.67
17 Months	495.83	5495.83
18 Months	525.00	5525.00
19 Months	554.17	5554.17
20 Months	583.33	5583.33
21 Months	612.50	5612.50
22 Months	641.67	5641.67
23 Months	670.83	5670.83
24 Months	700.00	5700.00
25 Months	729.17	5729.17
26 Months	758.33	5758.33
27 Months	787.50	5787.50
28 Months	816.67	5816.67
29 Months	845.83	5845.83
30 Months	875.00	5875.00
31 Months	904.17	5904.17
32 Months	933.33	5933.33
33 Months	962.50	5962.50
34 Months	991.67	5991.67
35 Months	1020.83	6020.83
36 Months	1050.00	6050.00
37 Months	1079.17	6079.17
38 Months	1108.33	6108.33
39 Months	1137.50	6137.50
40 Months	1166.67	6166.67
41 Months	1195.83	6195.83
42 Months	1225.00	6225.00
43 Months	1254.17	6254.17
44 Months	1283.33	6283.33
45 Months	1312.50	6312.50
46 Months	1341.67	6341.67
47 Months	1370.83	6370.83
48 Months	1400.00	6400.00
49 Months	1429.17	6429.17
50 Months	1458.33	6458.33
51 Months	1487.50	6487.50
52 Months	1516.67	6516.67
53 Months	1545.83	6545.83
54 Months	1575.00	6575.00
55 Months	1604.17	6604.17
56 Months	1633.33	6633.33
57 Months	1662.50	6662.50
58 Months	1691.67	6691.67
59 Months	1720.83	6720.83
60 Months	1750.00	6750.00

Duration	Interest	Final Amount
61 Months	1779.17	6779.17
62 Months	1808.33	6808.33
63 Months	1837.50	6837.50
64 Months	1866.67	6866.67
65 Months	1895.83	6895.83
66 Months	1925.00	6925.00
67 Months	1954.17	6954.17
68 Months	1983.33	6983.33
69 Months	2012.50	7012.50
70 Months	2041.67	7041.67
71 Months	2070.83	7070.83
72 Months	2100.00	7100.00
73 Months	2129.17	7129.17
74 Months	2158.33	7158.33
75 Months	2187.50	7187.50
76 Months	2216.67	7216.67
77 Months	2245.83	7245.83
78 Months	2275.00	7275.00
79 Months	2304.17	7304.17
80 Months	2333.33	7333.33
81 Months	2362.50	7362.50
82 Months	2391.67	7391.67
83 Months	2420.83	7420.83
84 Months	2450.00	7450.00
85 Months	2479.17	7479.17
86 Months	2508.33	7508.33
87 Months	2537.50	7537.50
88 Months	2566.67	7566.67
89 Months	2595.83	7595.83
90 Months	2625.00	7625.00
91 Months	2654.17	7654.17
92 Months	2683.33	7683.33
93 Months	2712.50	7712.50
94 Months	2741.67	7741.67
95 Months	2770.83	7770.83
96 Months	2800.00	7800.00
97 Months	2829.17	7829.17
98 Months	2858.33	7858.33
99 Months	2887.50	7887.50
100 Months	2916.67	7916.67
101 Months	2945.83	7945.83
102 Months	2975.00	7975.00
103 Months	3004.17	8004.17
104 Months	3033.33	8033.33
105 Months	3062.50	8062.50
106 Months	3091.67	8091.67
107 Months	3120.83	8120.83
108 Months	3150.00	8150.00
109 Months	3179.17	8179.17
110 Months	3208.33	8208.33
111 Months	3237.50	8237.50
112 Months	3266.67	8266.67
113 Months	3295.83	8295.83
114 Months	3325.00	8325.00
115 Months	3354.17	8354.17
116 Months	3383.33	8383.33
117 Months	3412.50	8412.50
118 Months	3441.67	8441.67
119 Months	3470.83	8470.83
120 Months	3500.00	8500.00

Frequently Asked Questions on Interest Calculator

What is Simple Interest?

Simple interest is interest that is only calculated on the principal either borrowed or deposited.
Generally, simple interest is set as a fixed percentage for the duration of a loan.
Calculate Total Amount (Principal + Interest).
A = P(1 + rt)

Simple interest equation / How to find the simple interest?

SI = P * ( 1 + RT).
P is Prinicipal, SI = Simple Interest Final Amount, R = interest rate / annum, T = time in years .

Simple Interest vs Compound Interest

Simple interest is calculated based on the principal, or original, amount of a loan.
Compound interest is calculated on the principal amount and the interest of period of time.

Formula to find interest rate / Solving for interest rate?

R = (1 / T) (A / P - 1).
R = Interest Rate, P is Prinicipal, A = Final Amount, T = time in years .

Simple interest examples

Calculate the Simple Interest if the principal amount is Rs. 10,000, the time period is 5 year and the rate is 3.875%.
Simple Interest, SI = P(1 + rt).
r = R / 100 = 3.875 % / 100 = 0.03875 per year.
A = 10000(1 + (0.03875 × 5)) , A = Rs. 11,937.50