Red Bloon Equivalent (RBE)

"RBE means Red Bloon Equivalent and tells you how many bloons you will have to pop in the current round."

- Round 5 in BTD4

Red Bloon Equivalent (RBE) is a new addition that debuted in Bloons Tower Defense 4. It displays how many Red Bloons would need to be popped to equal the amount of pops it would take to clear the current stage. So, for example, in the picture to the right fourteen pops are required to pass that particular Round. It also appears in Bloons TD 4 Expansion and Bloons Tower Defense 5. The lowest RBE in BTD4 is 11, the highest is 2881116 (Round 250 - no rounds were programmed after this). The final round has 999 B.F.B.s, and it is nearly impossible to survive, even if your entire screen is filled with Sun Gods, meaning Operation: Dart Storms are a must. In BTD5, all freeplay rounds have a random RBE past round 85, while the lowest is 3 (Round 24).

BTD1 RBE values

 * Round 1: 12 (12 Reds)
 * Round 2: 25 (25 Reds)
 * Round 3: 34 (24 Reds and 5 Blues)
 * Round 4: 58 (10 Reds, 24 Blues)
 * Round 5: 80 (30 Reds, 25 Blues)
 * Round 6: 45 (15 Greens )
 * Round 7: 150 (75 Blues)
 * Round 8: 251 (115 Reds, 68 Blues)
 * Round 9: 164 (49 Blues, 22 Greens)
 * Round 10: 120 (40 Greens)
 * Round 11: 96 (24 Yellows)
 * Round 12: 147 (30 Blues, 25 Green, 3 Yellows)
 * Round 13: 280 (40 Reds, 75 Blues, 30 Greens)
 * Round 14: 104 (26 Yellows)
 * Round 15: 240 (30 Blues, 60 Greens)
 * Round 16: 400 (80 Blues, 80 Greens)
 * Round 17: 390 (150 Blues, 30 Greens)
 * Round 18: 250 (30 Blues, 26 Greens, 28 Yellows)
 * Round 19: 276 (92 Greens)
 * Round 20: 360 (40 Blues, 60 Yellows)
 * Round 21: 395 (10 Blues, 85 Greens, 30 Yellows)
 * Round 22: 180 (45 Yellows)
 * Round 23: 361 (64 Yellows, 35 Greens)
 * Round 24: 340 (20 Blues, 60 Greens, 30 Yellows)
 * Round 25: 440 (80 Greens, 50 Yellows)
 * Round 26: 340 (85 Yellows)
 * Round 27: 180 (20 Blacks)
 * Round 28: 340 (40 Greens, 55 Yellows)
 * Round 29: 680 (125 Yellows, 20 Blacks)
 * Round 30: 756 (252 Greens)
 * Round 31: 447 (10 Blues, Greens, 28 Blacks)
 * Round 32: 362 (25 Greens, 20 Yellows, 23 Blacks)
 * Round 33: 600 (150 Yellows)
 * Round 34: 470 (35 Greens, 35 Yellows, 25 Blacks)
 * Round 35: 723 (85 Greens, 117 Yellows)
 * Round 36: 769 (118 Yellows, 33 Blacks)
 * Round 37: 531 (59 Blacks)
 * Round 38: 900 (225 Yellows)
 * Round 39: 860 (50 Reds, 50 Blues, 50 Greens, 50 Yellows, 40 Blacks)
 * Round 40: 720 (80 Blacks)
 * Round 41: 540 (20 Blacks, 40 Whites)
 * Round 42: 740 (50 Yellows, 30 Blacks, 30 Whites)
 * Round 43: 1400 (152 Yellows, 48 Blacks, 40 Whites)
 * Round 44: 1080 (120 Blacks)
 * Round 45: 1125 (125 Whites)
 * Round 46: 1320 (60 Yellows, 60 Blacks, 60 Whites)
 * Round 47: 1310 (80 Yellows, 70 Blacks, 40 Whites)
 * Round 48: 1648 (70 Yellows, 76 Blacks, 76 Whites)
 * Round 49: 1777 (100 Yellows, 83 Blacks, 70 Whites)
 * Round 50: 1800 (100 Blacks and 100 Whites)

BTD2 RBE values

 * Round 1: 12 (12 Reds)
 * Round 2: 30 (30 Reds)
 * Round 3: 31 (15 Reds, 8 Blues)
 * Round 4: 58 (10 Reds, 24 Blues)
 * Round 5: 78 (22 Reds, 28 Blues)
 * Round 6: 58 (13 Reds, 15 Greens)
 * Round 7: 100 (50 Blues)
 * Round 8: 85 (27 Reds, 29 Blues)
 * Round 9: 109 (32 Blues, 15 Greens)
 * Round 10: 96 (32 Greens)
 * Round 11: 80 (12 Greens, 11 Yellows)
 * Round 12: 37 (1 Rainbow)
 * Round 13: 202 (22 Reds, 42 Blues, 32 Greens)
 * Round 14: 88 (22 Yellows)
 * Round 15: 105 (15 Greens, 15 Yellows)
 * Round 16: 288 (54 Blues, 60 Greens)
 * Round 17: 215 (40 Blues, 54 Greens)
 * Round 18: 217 (30 Blues, 23 Greens, 22 Yellows)
 * Round 19: 215 (75 Greens)
 * Round 20: 19 (1 Lead)
 * Round 21: 344 (24 Blues, 40 Greens, 44 Yellows)
 * Round 22: 200 (50 Yellows)
 * Round 23: 214 (20 Blues, 30 Greens, 36 Yellows)
 * Round 24: 392 (20 Blues, 56 Greens, 46 Yellows)
 * Round 25: 303 (42 Yellows, 15 Blacks)
 * Round 26: 408 (102 Yellows)
 * Round 27: 252 (28 Blacks)
 * Round 28: 198 (11 Blacks, 11 Whites)
 * Round 29: 256 (11 Blacks, 9 Whites, 4 Leads)
 * Round 30: 480 (120 Yellows)
 * Round 31: 209 (11 Leads)
 * Round 32: 242 (20 Yellows, 10 Blacks, 8 Whites)
 * Round 33: 495 (55 Blacks)
 * Round 34: 632 (50 Yellows, 25 Blacks, 22 Whites)
 * Round 35: 259 (7 Rainbows)
 * Round 36: 457 (12 Yellows, 27 Blacks, 10 Whites, 4 Leads)
 * Round 37: 380 (20 Leads)
 * Round 38: 800 (200 Yellows)
 * Round 39: 969 (50 Yellows, 15 Blacks, 33 Whites, 8 Leads, 5 Rainbows)
 * Round 40: 540 (60 Blacks)
 * Round 41: 722 (18 Whites, 10 Leads, 10 Rainbows)
 * Round 42: 1290 (120 Yellows, 45 Blacks, 45 Whites)
 * Round 43: 1120 (20 Leads, 20 Rainbows)
 * Round 44: 1170 (130 Blacks)
 * Round 45: 990 (110 Whites)
 * Round 46: 665 (35 Leads)
 * Round 47: 1173 (35 Blacks, 35 Whites, 13 Leads, 8 Rainbows)
 * Round 48: 1238 (35 Blacks, 35 Whites, 32 Leads)
 * Round 49: 1110 (30 Rainbows)
 * Round 50: 1827 (28 Leads, 35 Rainbows)

BTD3 RBE values

 * Round 1: 14 (14 Reds)
 * Round 2: 30 (30 Reds)
 * Round 3: 31 (15 reds, 8 blues)
 * Round 4: 58 (10 reds, 24 blues)
 * Round 5: 78 (22 reds, 28 blues)
 * Round 6: 55 (10 reds, 15 green)
 * Round 7: 100 (50 Blues)
 * Round 8: 87 (27 reds, 30 blues)
 * Round 9: 109 (32 blues, 15 greens)
 * Round 10: 96 (32 Greens)
 * Round 11: 80 (12 greens, 11 yellows)
 * Round 12: 37 (1 Rainbow)
 * Round 13: 154 (18 reds, 38 blues, 30 greens)
 * Round 14: 85 (12 yellows, 1 rainbow)
 * Round 15: 126 (14 greens, 21 yellows)
 * Round 16: 211 (9 blues, 35 greens, 22 yellows)
 * Round 17: 245 (20 blues, 55 greens, 10 yellows)
 * Round 18: 244 (30 blues, 28 greens, 25 yellows)
 * Round 19: 235 (45 greens, 25 yellows)
 * Round 20: 95 (5 Leads)
 * Round 21: 316 (10 blues, 40 greens, 44 yellows)
 * Round 22: 200 (50 Yellows)
 * Round 23: 345 (35 greens, 60 yellows)
 * Round 24: 348 (20 blues, 56 greens, 45 yellows)
 * Round 25: 303 (42 yellows, 15 blacks)
 * Round 26: 801 (100 yellows, 15 blacks, 14 leads)
 * Round 27: 315 (35 Blacks)
 * Round 28: 315 (19 blacks, 16 Whites)
 * Round 29: 348 (12 blacks, 14 whites, 6 leads)
 * Round 30: 504 (60 yellows, 28 blacks)
 * Round 31: 164 (2 Ceramics)
 * Round 32: 422 (20 yellows, 22 blacks, 16 whites)
 * Round 33: 786 (60 blacks, 3 ceramics)
 * Round 34: 978 (50 yellows, 25 blacks, 25 whites, 4 ceramics)
 * Round 35: 444 (12 Rainbows)
 * Round 36: 616 (12 yellows, 30 blacks, 12 whites, 10 leads)
 * Round 37: 458 (1 M.O.A.B)
 * Round 38: 1100 (60 yellows, 50 blacks, 5 ceramics)
 * Round 39: 1344 (50 yellows, 22 blacks, 47 whites, 10 leads, 9 rainbows)
 * Round 40: 986 (64 blacks, 5 ceramics)
 * Round 41: 1020 (18 whites, 14 leads, 16 rainbows)
 * Round 42: 1706 (100 yellows, 54 blacks, 10 ceramics)
 * Round 43: 1641 (20 leads, 23 rainbows, 5 ceramics)
 * Round 44: 2038 (5 ceramics, 130 blacks, 1 M.O.A.B)
 * Round 45: 1712 (90 whites, 11 ceramics)
 * Round 46: 2488 (38 leads, 30 rainbows, 8 ceramics)
 * Round 47: 2421 (20 blacks, 40 whites, 18 leads, 15 rainbows, 12 ceramics)
 * Round 48: 2384 (30 blacks, 30 whites, 25 leads, 37 rainbows)
 * Round 49: 3062 (34 rainbows, 22 ceramics)
 * Round 50: 3322 (16 leads, 28 rainbows, 13 ceramics, 2 M.O.A.B)

BTD4 RBE values
(Rounds after 250 are not programmed on this game.)
 * Round 1 RBE: 14 (14 Reds)
 * Round 2 RBE: 30 (30 Reds)
 * Round 3 RBE: 30 (20 Reds, 5 Blues)
 * Round 4 RBE: 60 (30 Reds, 15 Blues)
 * Round 5 RBE: 45 (5 Reds, 20 Blues)
 * Round 6 RBE: 57 (15 Reds, 15 Blues, 4 Greens)
 * Round 7 RBE: 85 (20 Reds, 25 Blues, 5 Greens)
 * Round 8 RBE: 101 (10 Reds, 20 Blues, 17 Greens)
 * Round 9 RBE: 79 (10 Reds, 12 Blues, 15 Greens)
 * Round 10 RBE: 200 (100 Blues)
 * Round 11 RBE: 69 (5 Reds, 10 Blues, 12 Greens, 2 Yellows)
 * Round 12 RBE: 80 (15 Blues, 10 Greens, 5 Yellows)
 * Round 13 RBE: 135 (20 Reds, 25 Greens, 10 Yellows)
 * Round 14 RBE: 150 (15 Reds, 15 Blues, 15 Greens, 15 Yellows)
 * Round 15 RBE: 120 (20 Reds, 15 Greens, 10 Yellows, 3 Pinks)
 * Round 16 RBE: 137 (20 Greens, 13 Yellows, 5 Pinks)
 * Round 17 RBE: 182 (15 Greens, 28 Yellows, 5 Pinks)
 * Round 18 RBE: 240 (80 Greens)
 * Round 19 RBE: 125 (5 Greens, 10 Yellows, 14 Pinks)
 * Round 20 RBE: 88 (8 Blacks)
 * Round 21 RBE: 80 (16 Pinks)
 * Round 22 RBE: 99 (9 Whites)
 * Round 23 RBE: 121 (6 Blacks, 5 Whites)
 * Round 24 RBE: 11 (1 Camo)
 * Round 25 RBE: 138 (6 Zebras)
 * Round 26 RBE: 167 (10 Yellows, 10 Pinks, 4 Blacks, 3 Whites)
 * Round 27 RBE: 400 (100 Yellows)
 * Round 28 RBE: 230 (3 Zebras, 7 Leads)
 * Round 29 RBE: 350 (70 Pinks)
 * Round 30 RBE: 230 (10 Leads)
 * Round 31 RBE: 414 (18 Zebras)
 * Round 32 RBE: 789 (25 Blacks, 30 Whites, 8 Leads)
 * Round 33 RBE: 550 (50 Camo)
 * Round 34 RBE: 322 (14 Zebras)
 * Round 35 RBE: 826 (35 Pinks, 25 Whites, 8 Rainbows)
 * Round 36 RBE: 450 (90 Pinks)
 * Round 37 RBE: 1130 (20 Blacks, 20 Whites, 15 Zebras, 15 Leads)
 * Round 38 RBE: 1612 (20 Whites, 16 Zebras, 20 Leads, 12 Rainbows)
 * Round 39 RBE: 2174 (10 Blacks, 10 Whites, 20 Zebras, 20 Leads, 22 Rainbows)
 * Round 40 RBE: 902 (20 Reds, 10 Rainbows, 4 Ceramics)
 * Round 41 RBE: 1760 (80 Blacks, 80 Whites)
 * Round 42 RBE: 2330 (40 Leads, 30 Rainbows)
 * Round 43 RBE: 1500 (10 Rainbows, 10 Ceramics)
 * Round 44 RBE: 1765 (30 Whites, 40 Zebras, 5 Ceramics)
 * Round 45 RBE: 2359 (200 Pinks, 8 Leads, 25 Rainbows)
 * Round 46 RBE: 613 (1 M.O.A.B.)
 * Round 47 RBE: 2830 (70 Camo, 20 Ceramics)
 * Round 48 RBE: 3670 (120 Camo, 50 Rainbows)
 * Round 49 RBE: 3928 (10 Camo, 20 Zebras, 32 Rainbows, 18 Ceramics)
 * Round 50 RBE: 3490 (20 Reds, 8 Leads, 20 Ceramics, 2 M.O.A.B.)
 * Round 51 RBE: 3354 (10 Rainbows, 28 Ceramics)
 * Round 52 RBE: 3431 (25 Rainbows, 10 Ceramics, 2 M.O.A.B.)
 * Round 53 RBE: 2913 (11 Reds, 50 Camo, 4 M.O.A.B.)
 * Round 54 RBE: 4831 (35 Ceramics, 2 M.O.A.B.)
 * Round 55 RBE: 4726 (12 Leads, 40 Rainbows, 19 Ceramics, 1 M.O.A.B.)
 * Round 56 RBE: 8828 (120 Rainbows, 25 Ceramics, 1 M.O.A.B.)
 * Round 57 RBE: 5877 (40 Rainbows, 15 Ceramics, 4 M.O.A.B.)
 * Round 58 RBE: 5074 (25 Rainbows, 20 Ceramics, 3 M.O.A.B.)
 * Round 59 RBE: 5150 (50 Ceramics)
 * Round 60 RBE: 2884 (1 B.F.B)
 * Round 61 RBE: 4970 (40 Rainbows, 30 Ceramic)
 * Round 62 RBE: 3426 (200 Camos, 2 M.O.A.B.)
 * Round 63 RBE: 6575 (18 Leads, 50 Rainbow, 37 Ceramic)
 * Round 64 RBE: 4291 (7 M.O.A.B.)
 * Round 65 RBE: 7936 (100 Zebras, 50 Rainbow, 20 Ceramic, 2 M.O.A.B.)
 * Round 66 RBE: 5517 (9 M.O.A.B.)
 * Round 67 RBE: 7703 (28 Reds, 15 Ceramic, 10 M.O.A.B.)
 * Round 68 RBE: 5350 (14 Reds, 4 M.O.A.B., 1 B.F.B.)
 * Round 69 RBE: 10990 (30 Leads, 100 Ceramic)
 * Round 70 RBE: 11239 (200 Rainbows, 3 M.O.A.B.)
 * Round 71 RBE: 9220 (30 Ceramics, 10 M.O.A.B.)
 * Round 72 RBE: 5798 (30 Reds, 2 B.F.B.)
 * Round 73 RBE: 7219 (44 Reds, 7 M.O.A.B., 1 B.F.B.)
 * Round 74 RBE: 23484 (200 Ceramics, 1 B.F.B.)
 * Round 75 RBE: 11762 (14 Reds, 28 Lead, 4 M.O.A.B., 3 B.F.B.)
 * Round 76+: The RBE will get random as each player will face freeplay mode which will have random bloon spawns from Zebras to B.F.B.s. Leads not included.
 * Round 100+: From now on the rounds will be extremely long. Expect masses of MOAB's BFB's and Ceramics.
 * Round 250 RBE: 2881116 (999 B.F.B.'s)

BTD5 RBE values

 * Round 1 RBE: 20 (20 Reds)
 * Round 2 RBE: 30 (30 Reds)
 * Round 3 RBE: 30 (20 Reds, 5 Blues)
 * Round 4 RBE: 60 (30 Reds, 15 Blues)
 * Round 5 RBE: 55 (5 Reds, 25 Blues)
 * Round 6 RBE: 57 (15 Reds, 15 Blues, 4 Greens)
 * Round 7 RBE: 85 (20 Reds, 25 Blues, 5 Greens)
 * Round 8 RBE: 92 (10 Reds, 20 Blues, 14 Greens)
 * Round 9 RBE: 90 (30 Greens)
 * Round 10 your mum is GAYYY: 204 (102 Blues with dense final rush)
 * Round 11 RBE: 74 (10 Reds, 10 Blues, 12 Greens, 2 Yellows)
 * Round 12 RBE: 80 (15 Blues, 10 Greens, 5 Yellows)
 * Round 13 RBE: 185 (100 Reds, 23 Greens, 4 Yellows)
 * Round 14 RBE: 145 (49 Reds, 15 Blues, 10 Greens, 9 Yellows)
 * Round 15 RBE: 91 (20 Reds, 12 Greens, 5 Yellows, 3 Pinks)
 * Round 16 RBE: 112 (20 Greens, 8 Yellows, 4 Pinks)
 * Round 17 RBE: 32 (8 Yellow Regrowth)
 * Round 18 RBE: 240 (80 Greens, dense final rush)
 * Round 19 RBE: 101 (10 Greens, 4 Yellows, 5 Yellow Regrowth, 7 Pinks)
 * Round 20 RBE: 66 (6 Blacks)
 * Round 21 RBE: 70 (14 Pinks)
 * Round 22 RBE: 88 (8 Whites)
 * Round 23 RBE: 99 (5 Blacks, 4 Whites)
 * Round 24 RBE: 3 (1 Green Camo)
 * Round 25 RBE: 124 (31 Yellow Regrowth)
 * Round 26 RBE: 207 (23 Pinks, 4 Zebras)
 * Round 27 RBE: 545 (120 Reds, 55 Blues, 45 Greens, 45 Yellows)
 * Round 28 RBE: 92 (4 Leads)
 * Round 29 RBE: 160 (25 Yellows, 12 Pink Regrowth)
 * Round 30 RBE: 207 (9 Leads)
 * Round 31 RBE: 230 (8 Zebras, 2 Zebra Regrowth)
 * Round 32 RBE: 767 (25 Blacks, 28 Whites, 8 Leads)
 * Round 33 RBE: 80 (20 Yellow Camo)
 * Round 34 RBE: 675 (140 Yellows, 5 Zebras)
 * Round 35 RBE: 685 (35 Pinks, 25 Whites, 5 Rainbows)
 * Round 36 RBE: 405 (81 Pinks)
 * Round 37 RBE: 1092 (20 Blacks, 20 Whites, 7 White Camo, 15 Leads, 10 Zebras)
 * Round 38 RBE: 1137 (42 Pink Regrowth, 17 Whites, 14 Leads, 10 Zebras, 4 Rainbows)
 * Round 39 RBE: 1986 (10 Blacks, 10 Whites, 20 Leads, 20 Zebras, 18 Rainbows)
 * Round 40 RBE: 886 (10 Rainbows, 4 Ceramics)
 * Round 41 RBE: 2040 (60 Blacks, 60 Zebras)
 * Round 42 RBE: 564 (6 Rainbow Camo, 6 Rainbow Regrowth)
 * Round 43 RBE: 1198 (10 Rainbows, 7 Ceramics)
 * Round 44 RBE: 1150 (50 Zebras)
 * Round 45 RBE: 2359 (200 Pinks, 8 Leads, 25 Rainbows)
 * Round 46 RBE: 616 (1 M.O.A.B.)
 * Round 47 RBE: 1598 (70 Pink Camo, 12 Ceramics)
 * Round 48 RBE: 2950 (120 Pink Regrowth, 50 Rainbows)
 * Round 49 RBE: 4771 (343 Greens, 20 Zebras, 20 Rainbows, 10 Rainbow Regrowth, 18 Ceramics)
 * Round 50 RBE: 3516 (20 Reds, 8 Leads, 20 Ceramics, 2 M.O.A.B)
 * Round 51 RBE: 3382 (10 Rainbow Regrowth, 28 Ceramic)
 * Round 52 RBE: 3447 (25 Rainbows, 10 Ceramics, 2 M.O.A.B)
 * Round 53 RBE: 2248 (80 Pink Camo, 3 M.O.A.B)
 * Round 54 RBE: 4872 (35 Ceramics, 2 M.O.A.B)
 * Round 55 RBE: 5296 (45 Ceramics, 1 M.O.A.B)
 * Round 56 RBE: 2496 (40 Rainbow Regrowth, 1 M.O.A.B)
 * Round 57 RBE: 4344 (40 Rainbows, 4 M.O.A.B)
 * Round 58 RBE: 6096 (29 Ceramics, 5 M.O.A.B)
 * Round 59 RBE: 5844 (28 Lead Camo, 50 Ceramic)
 * Round 60 RBE: 3164 (1 B.F.B.)
 * Round 61 RBE: 6530 (150 Zebra Regrowth, 5 M.O.A.B)
 * Round 62 RBE: 5901 (300 Pink Camos, 15 Rainbow Camo Regrowth, 6 M.O.A.B)
 * Round 63 RBE: 14413 (75 Leads, 122 Ceramics)
 * Round 64 RBE: 5544 (9 M.O.A.B)
 * Round 65 RBE: 18966 (100 Zebras, 70 Rainbows, 50 Ceramics, 3 M.O.A.B, 2 B.F.B)
 * Round 66 RBE: 7392 (12 M.O.A.B)
 * Round 67 RBE: 7720 (15 Ceramics, 10 M.O.A.B)
 * Round 68 RBE: 5628 (4 M.O.A.B, 1 B.F.B)
 * Round 69 RBE: 8660 (60 Leads, 70 Ceramic Regrowth)
 * Round 70 RBE: 11864 (200 Rainbow Camo, 4 M.O.A.B)
 * Round 71 RBE: 9280 (30 Ceramics, 10 M.O.A.B)
 * Round 72 RBE: 10280 (38 Ceramic Regrowth, 2 B.F.B)
 * Round 73 RBE: 11872 (9 M.O.A.B, 2 B.F.B)
 * Round 74 RBE: 23964 (200 Ceramics, 1 B.F.B)
 * Round 75 RBE: 12600 (28 Leads, 4 M.O.A.B, 3 B.F.B)
 * Round 76 RBE: 6240 (60 Ceramic Regrowth)
 * Round 77 RBE: 24444 (14 M.O.A.B, 5 B.F.B)
 * Round 78 RBE: 25502 (150 Rainbows, 75 Ceramics, 72 Ceramic Camos, 1 B.F.B)
 * Round 79 RBE: 45648 (500 Rainbow Regrowth, 7 B.F.B)
 * Round 80 RBE: 19096 (31 M.O.A.B)
 * Round 81 RBE: 28476 (9 B.F.B)
 * Round 82 RBE: 50440 (400 Rainbow Camo Regrowth, 10 B.F.B)
 * Round 83 RBE: 34080 (150 Ceramics, 30 M.O.A.B)
 * Round 84 RBE: 62440 (50 M.O.A.B, 10 B.F.B)
 * Round 85 RBE: 16656 (1 Z.O.M.G.) *Impoppable round 85 RBE: 83280 (5 Z.O.M.G.s)
 * Round 86+: The RBE will get random as each player will face freeplay mode which will have random bloon spawns from Ceramics to ZOMGs. Unlike BTD4, there are infinite rounds.

Index
Red:

1-5, 8, 13, 39 (1)

1-6, 8, 13(2&3)

1-9, 11, 13-15, 40, 50, 53, 67-68, 72-73, 75 (4)

1-8, 11, 13-15, 27, 50 (5)

Blue:

3-5, 7-9, 12-13, 15-18, 20-21, 24, 31, 39 (1)

3-5, 7-9, 13, 16-18, 21, 23-24 (2)

3-5, 7-9, 13, 16-18, 21, 24 (3)

3-12, 14 (4)

3-8, 10-12, 14, 27 (5)

Green:

6, 9-10, 12-13, 15-19, 21, 23-25, 28, 30-32, 34-35, 39(1)

6, 9-11, 13, 15-19, 21, 23-24(2&3)

6-9, 11-19 (4)

6-9, 11-19, 24, 27, 49 (5)

Yellow:

11-12, 14, 18, 20-26, 28-29, 32-36, 38-39, 42-43, 46-49(1)

11, 14-15, 18, 21-26, 30, 32, 34, 36, 38-39, 42 (2)

11, 14-19, 21-26, 30, 32, 34, 36, 38-39, 42 (3)

11-17, 19, 26-27 (4)

11-17, 19, 25, 27, 29, 33-34 (5)

Pink:

15-17, 19, 21, 26, 29, 35-36, 45 (4)

15-16, 19, 21, 26, 29, 35-36, 38, 45, 47-48, 53, 62 (5)

Black:

27, 29, 31-32, 34, 36-37, 39-44, 46-50 (1)

25, 27-29, 32-34, 36, 39-40, 42, 44, 47-48 (2)

25-30, 32-34, 36, 38-40, 42, 44, 47-48(3)

20, 23, 26, 32, 37, 39, 41(4&5)

White:

41-43, 45-50(1)

28-29, 32, 34, 36, 39, 41-42, 45, 47-48(2)

28-29, 32, 34, 36, 39, 41, 45, 47-48(3)

22-23, 26, 32, 35, 37, 39, 41, 44(4)

22-23, 32, 35, 37-39(5)

Camo bloon:

24, 33, 47-49, 53, 62

Lead:

20, 29, 31, 36-37, 39, 41, 43, 46-48, 50 (2)

20, 26, 29, 36, 39, 41, 43, 46-48, 50 (3)

28, 30, 32, 37-39, 42, 45, 50, 55, 63, 69, 75 (4)

28, 30, 32, 37-39, 42, 45, 50, 59, 63, 69, 75 (5)

Zebra:

25, 28, 31, 34, 37-39, 44, 49, 65, 75(4)

26, 31, 34, 37-39, 41, 44, 49, 61, 65(5)

Rainbow:

12, 35, 39, 41, 43, 47, 49-50 (2)

12, 14, 35, 39, 41, 43, 46-50 (3)

35, 38-40, 42-43, 45, 48-49, 51-52, 55-58, 61, 63, 65, 70 (4)

35, 38-40, 42-43, 45, 48-49, 51-52, 56-57, 62, 65, 70, 78-79, 82(5)

Ceramic:

31, 33-34, 38, 40, 42-47, 49-50(3)

40, 43-44, 47, 49-52, 54-59, 61, 63, 65, 67, 69, 71-250 (4)

40, 43, 47, 49-52, 54-55, 58-59, 63, 65, 67, 69, 71-72, 74, 76, 78, 83, 86+ (5)

M.O.A.B:

37, 44, 50 (3)

46, 50, 52-58, 62, 64-68, 70, 71, 73, 75-250 (4)

46,50, 52-58, 61-62, 64-68, 70-71, 73, 75, 77, 80, 83-84, 86+ (5)

B.F.B:

60, 68, 72+ (4)

60, 65, 68, 72-75, 77-79, 81-82, 84, 86+ (5)

Z.O.M.G:

85+

Types
Camo:

24, 33, 37, 42, 47, 53, 59, 62, 70, 78, 82

Regrowth:

17, 19, 25, 29, 31, 38, 42, 48-49, 51, 56, 61-62, 69, 72, 76, 79, 82

Camo Regrowth:

62, 82

Trivia

 * The lowest RBE (as of now) is 3, the green camo on round 24 in Bloons TD 5.
 * In Bloons TD 4, the RBE of the Camo Bloon in Round 24 should be 11, yet the in-game RBE says 9.
 * In BTD5, rounds 21 and 36 are the only rounds that consist entirely of Pink Bloons.
 * In BTD5, some Daily Challenges have a modified RBE.
 * RBE is sometimes confused to stand for Rate Bloons Explode.
 * The second lowest RBE (as of now) is 11 on round 24 in BTD4 as mentioned above.