You don’t need (or want) hundreds of sit ups a day. For most people, a focused 10–40 total reps on the days you train abs is plenty, as long as form is good and you’re mixing in other core work.

Quick Scoop

  • There’s no single “magic” number; it depends on your level and goals.
  • Many coaches suggest starting with 2–3 sets of 8–15 sit ups (around 10–30 total reps).
  • As you get stronger, a common target is up to about 30–40 sit ups on a training day for most adults, not hundreds.
  • You can do sit ups most days if your form is strict and your lower back feels fine, but you don’t need to do them daily for results.
  • Strong, visible abs come more from overall training and diet than from sit up volume alone.

Simple Daily Guide (By Level)

These are ballpark ranges, not medical advice. If you have any back, neck, or hip issues, check with a professional first.

  • Beginner
    • 2–3 sets of 8–12 sit ups (about 10–25 total reps).
* Do this 2–4 days per week, not necessarily every day.
  • Intermediate
    • 2–3 sets of 12–20 sit ups (about 20–40 total reps).
* Train abs 3–4 days per week, adding variations (twist sit ups, incline, etc.).
  • Advanced
    • Still keep the total reasonable (for example 30–40 controlled reps), but increase difficulty with weight, tempo, or harder variations instead of huge numbers.

A simple example plan:

  • Monday, Wednesday, Friday: 3 sets of 12–15 sit ups + planks, instead of doing 200 sit ups every day.

Why “More” Sit Ups Isn’t Better

  • Sit ups mainly hit the rectus abdominis (the six‑pack muscles), not all your core.
  • Very high daily volume, especially with fast, sloppy reps, can stress your lower back and neck.
  • You’ll get better results mixing in:
    • Planks and side planks
    • Bicycle crunches
    • Glute bridges and dead bugs

Think of sit ups as one tool in a full‑body routine, not the whole program.

If Your Goal Is…

  • General fitness / basic core strength
    • 2–3 sit up sessions per week, 2–3 sets of 10–15 reps, plus other core moves.
  • Stronger abs
    • 3 sets of 15–20 sit ups, 2–3 times per week, adding resistance or harder variations once this feels easy.
  • Flat or visible abs
    • You can’t spot‑reduce belly fat with sit ups; you need overall calorie control, full‑body training, and consistent movement.
* Sit ups are for muscle, not direct fat loss.

Mini “Forum-Style” Take

“I used to do 100+ sit ups a day and my back hated me. Switched to 3×15 slow, controlled sit ups plus planks a few times a week. Better results, no pain.” (Typical advice you’ll see echoed in many fitness discussions.)

TL;DR:
For “how many sit ups a day,” a smart range for most people is around 10–40 controlled reps on the days you train abs, 2–4 times per week, combined with other core exercises and good overall training and nutrition.

Information gathered from public forums or data available on the internet and portrayed here.