MP3 to MIDI Free-Tier Limits: What a Four-Minute Song Needs
A four-minute song is 240 seconds. Each site below publishes a maximum length; none publishes what that maximum means for a particular track. Here the substitution is done: one 240-second song, put through four published entry points.
The short answer
- Two of the four caps hold the song in one upload: jukeblocks' Recreate path at 8 minutes, ai-midi's free tier at 5. The other two fail, the 3-minute cap by 60 seconds.
- Exactly one takes the song whole and costs nothing: ai-midi's free tier, rationed to one full MIDI download a week.
- The 30-second cap needs 8 uploads for this song, putting 7 cut points inside it.
- File size refuses one of the four: a four-minute 24-bit WAV is about 60 MB, over ai-midi's free 50 MB ceiling.
The four entry points, with the song substituted in
| Entry point | Published length cap | Published size cap | Uploads for 240 s | Slack against 240 s | What it costs |
|---|---|---|---|---|---|
| songscription.ai free tier |
30 seconds per transcription | Not stated | 8 | 210 s short, per upload | Free, unlimited in number of clips |
| jukeblocks.io free browser tool |
3 minutes (180 s) | 100 MB | 2 | 60 s short | Free; runs in the browser, nothing uploaded |
| jukeblocks.io Recreate |
8 minutes (480 s) | 100 MB | 1 | 240 s spare | 1 converter credit per song, returned if the job fails |
| ai-midi.com free tier |
5 minutes (300 s) | 50 MB | 1 | 60 s spare | One full MIDI download per week |
Caps and prices are each site's own published figures, read in September 2026. The uploads and slack columns are arithmetic on 240 seconds, which no site publishes.
What the arithmetic means in practice
The 30-second cap is the only one that changes the shape of the job. 240 divided by 30 is 8 with nothing left over, so the song leaves as eight clips and carries 7 boundaries. A note still sounding when a boundary falls arrives as two notes, one in each clip.
The 3-minute cap fails as a step, not a slope: a 3:00 file fits and a 3:01 file does not. There is no partial acceptance, so 240 seconds becomes at least 2 files.
The 5-minute and 8-minute caps both accept the song whole. What separates them is the price of a repeat: ai-midi's free tier allows one full MIDI download a week, while jukeblocks' Recreate path rations nothing and charges per song.
The size ceiling refuses one of the four
A stereo WAV at 44.1 kHz runs roughly 10 MB per minute at 16-bit and around 15 MB per minute at 24-bit, so four minutes is about 40 MB and about 60 MB. Both fit the two 100 MB ceilings; only the 40 MB version fits ai-midi's free 50 MB ceiling. The same song exported at 24-bit is therefore accepted by three of the four entry points and refused by one, and bit depth rather than running time decides it.
What the song costs once the free tier runs out
ai-midi charges paid usage at 1 credit per begun five-second block, with a 12-credit minimum per job. 240 seconds is 48 blocks of five seconds, so the song is 48 credits, well above the minimum. The $9.99 monthly plan carries 720 credits, or 15 songs of this length; $19.99 carries 1,800, or 37 whole songs; $39.99 carries 4,320, or 90. jukeblocks' Recreate path is flat by comparison: 1 credit per song, returned when a job fails.
Questions
- So which one should I use?
- If it has to be free and arrive whole, ai-midi's free tier is the only one of the four that does both, and it gives you one song a week. If it has to be free and repeatable, songscription's free tier caps no number of clips, but the song arrives as 8 pieces.
- Where do these numbers come from?
- The caps, the credit rate and the file-size figures are each site's own published values. Dividing by 240 seconds is this page's.