Seasons
Season 1 episodes — IMDb ratings
| # | Title | Rating | Votes |
|---|
| 0 | Unaired Premiere Episode | 8.2 | 1,058 |
| 1 | Chapter One 'Genesis' | 8.1 | 3,282 |
| 2 | Chapter Two 'Don't Look Back' | 8.0 | 2,513 |
| 3 | Chapter Three 'One Giant Leap' | 8.0 | 2,315 |
| 4 | Chapter Four 'Collision' | 8.1 | 2,220 |
| 5 | Chapter Five 'Hiros' | 8.1 | 2,160 |
| 6 | Chapter Six 'Better Halves' | 7.7 | 2,044 |
| 7 | Chapter Seven 'Nothing to Hide' | 7.8 | 2,001 |
| 8 | Chapter Eight 'Seven Minutes to Midnight' | 7.9 | 2,021 |
| 9 | Chapter Nine 'Homecoming' | 8.6 | 2,229 |
| 10 | Chapter Ten 'Six Months Ago' | 8.3 | 2,089 |
| 11 | Chapter Eleven 'Fallout' | 8.4 | 2,023 |
| 12 | Chapter Twelve 'Godsend' | 7.9 | 1,964 |
| 13 | Chapter Thirteen 'The Fix' | 7.8 | 1,911 |
| 14 | Chapter Fourteen 'Distractions' | 8.1 | 1,934 |
| 15 | Chapter Fifteen 'Run!' | 7.9 | 1,924 |
| 16 | Chapter Sixteen 'Unexpected' | 8.3 | 1,984 |
| 17 | Chapter Seventeen 'Company Man' | 8.9 | 2,628 |
| 18 | Chapter Eighteen 'Parasite' | 8.5 | 2,165 |
| 19 | Chapter Nineteen '.07%' | 8.3 | 2,057 |
| 20 | Chapter Twenty 'Five Years Gone' | 9.0 | 2,914 |
| 21 | Chapter Twenty-One 'The Hard Part' | 8.1 | 1,969 |
| 22 | Chapter Twenty-Two 'Landslide' | 8.4 | 1,978 |
| 23 | Chapter Twenty-Three 'How to Stop an Exploding Man' | 8.4 | 2,804 |
Season 2 episodes — IMDb ratings
| # | Title | Rating | Votes |
|---|
| 1 | Chapter One 'Four Months Later...' | 7.7 | 2,198 |
| 2 | Chapter Two 'Lizards' | 7.5 | 1,680 |
| 3 | Chapter Three 'Kindred' | 7.5 | 1,638 |
| 4 | Chapter Four 'The Kindness of Strangers' | 7.5 | 1,502 |
| 5 | Chapter Five 'Fight or Flight' | 7.6 | 1,555 |
| 6 | Chapter Six 'The Line' | 7.3 | 1,450 |
| 7 | Chapter Seven 'Out of Time' | 7.8 | 1,502 |
| 8 | Chapter Eight 'Four Months Ago...' | 7.9 | 1,566 |
| 9 | Chapter Nine: Cautionary Tales | 8.1 | 1,578 |
| 10 | Chapter Ten 'Truth & Consequences' | 7.6 | 1,462 |
| 11 | Chapter Eleven 'Powerless' | 7.9 | 1,652 |
Season 3 episodes — IMDb ratings
| # | Title | Rating | Votes |
|---|
| 1 | Chapter One 'The Second Coming' | 7.6 | 1,891 |
| 2 | Chapter Two 'The Butterfly Effect' | 7.5 | 1,522 |
| 3 | Chapter Three 'One of Us, One of Them' | 7.4 | 1,413 |
| 4 | Chapter Four 'I Am Become Death' | 7.5 | 1,426 |
| 5 | Chapter Five 'Angels and Monsters' | 7.3 | 1,346 |
| 6 | Chapter Six 'Dying of the Light' | 7.4 | 1,344 |
| 7 | Chapter Seven 'Eris Quod Sum' | 7.2 | 1,246 |
| 8 | Chapter Eight 'Villains' | 7.6 | 1,338 |
| 9 | Chapter Nine 'It's Coming' | 7.3 | 1,240 |
| 10 | Chapter Ten 'The Eclipse Part 1' | 7.4 | 1,244 |
| 11 | Chapter Eleven 'The Eclipse - Part 2' | 7.4 | 1,249 |
| 12 | Chapter Twelve 'Our Father' | 7.8 | 1,318 |
| 13 | Chapter Thirteen 'Dual' | 7.5 | 1,336 |
| 14 | Chapter One 'A Clear and Present Danger' | 7.6 | 1,298 |
| 15 | Chapter Two 'Trust and Blood' | 7.4 | 1,216 |
| 16 | Chapter Three 'Building 26' | 7.1 | 1,164 |
| 17 | Chapter Four 'Cold Wars' | 7.0 | 1,128 |
| 18 | Chapter Five 'Exposed' | 7.1 | 1,144 |
| 19 | Chapter Six 'Shades of Gray' | 7.4 | 1,151 |
| 20 | Chapter Seven 'Cold Snap' | 7.8 | 1,292 |
| 21 | Chapter Eight 'Into Asylum' | 7.2 | 1,153 |
| 22 | Chapter Nine 'Turn and Face the Strange' | 7.4 | 1,104 |
| 23 | Chapter Ten '1961' | 7.2 | 1,219 |
| 24 | Chapter Eleven 'I Am Sylar' | 7.4 | 1,026 |
| 25 | Chapter Twelve 'An Invisible Thread' | 7.5 | 1,268 |
Season 4 episodes — IMDb ratings
| # | Title | Rating | Votes |
|---|
| 1 | Chapter One 'Orientation/Jump, Push, Fall' | 7.4 | 1,200 |
| 2 | Chapter Two 'Ink' | 7.2 | 1,019 |
| 3 | Chapter Three 'Acceptance' | 7.1 | 991 |
| 4 | Chapter Four 'Hysterical Blindness' | 7.4 | 1,009 |
| 5 | Chapter Five 'Tabula Rasa' | 7.3 | 980 |
| 6 | Chapter Six 'Strange Attractors' | 7.1 | 967 |
| 7 | Chapter Seven 'Once Upon a Time in Texas' | 7.5 | 1,016 |
| 8 | Chapter Eight 'Shadowboxing' | 7.4 | 950 |
| 9 | Chapter Nine 'Brother's Keeper' | 7.3 | 929 |
| 10 | Chapter Ten 'Thanksgiving' | 7.2 | 930 |
| 11 | Chapter Eleven 'The Fifth Stage' | 7.2 | 961 |
| 12 | Chapter Twelve 'Upon This Rock' | 6.9 | 918 |
| 13 | Chapter Thirteen 'Let It Bleed' | 6.8 | 936 |
| 14 | Chapter Fourteen 'Close to You' | 6.9 | 924 |
| 15 | Chapter Fifteen 'Pass/Fail' | 6.8 | 977 |
| 16 | Chapter Sixteen 'The Art of Deception' | 7.2 | 922 |
| 17 | Chapter Seventeen 'The Wall' | 7.4 | 961 |
| 18 | Chapter Eighteen 'Brave New World' | 7.6 | 1,318 |
