100-envelope challenge
Fill 100 envelopes numbered 1 through 100. Envelope N gets $N inside. When you're done, you've saved $5,050. Tap a cell to mark that envelope filled — the tracker below saves to your browser so you can come back to it.
Saved to your browser. Tap a cell to mark it done. Print this page for a paper tracker.
Why the challenge went viral
The math is elementary — the sum of 1 through 100 is 5,050 — but the format turns saving into a game with a visible finish line. Every filled envelope is a small, physical win, and the largest amounts get concentrated in the final envelopes when momentum is highest.
Common variations
- Weekly draw: pick one envelope a week instead of one a day. Same $5,050, takes about two years.
- Reverse mode: start with envelope 100 to front-load the pain. If you make it past the first month, the rest is easy.
- Half challenge: envelopes 1–50 only. Saves $1,275. Good for tighter budgets.
Practical tips
Pick envelopes at random rather than in order — otherwise you'll do the small ones first and stall on the big ones. Keep the filled envelopes physically separate from spending money. When done, deposit the total into a real savings account so you're not keeping $5,050 in cash.
- 52-week savings challenge
- Sinking funds— Where to send the $5,050 when you're done
Common questions
›How does the 100-envelope challenge work?
Number 100 envelopes 1 through 100. Each day, pick one at random, put that many dollars in, and set it aside. When all 100 are filled you've saved $5,050 (1+2+…+100).
›Is 100 days too aggressive?
For many people, yes. Common variants: pick one envelope per week (~2 years, still $5,050), or cap the daily amount at $25 (still adds up meaningfully). The tracker below works for any pace.
›Do I have to use cash?
No. A savings account with a simple ledger works the same way. The envelopes are a visual — this page turns them into a digital grid that saves to your device.
Take it with you.
Download as Excel